what is the desertion hypothesis

What is desertification and why is it important to understand?

Currently, around 2 billion people live in drylands, which are most prone to desertification, according to Earth.org. Image:  REUTERS/Ivan Alvarado

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Stay up to date:, sdg 15: life on land.

• Factors including climate change, deforestation, overgrazing and unsustainable agricultural practices are increasingly turning our world’s drylands into deserts.
• Degradation of productive soil along with the loss of biodiversity, bodies of water and vegetation also impacts human life, leading to poverty, food and water scarcity and poor health.
• But 2024 could become a seminal year for the fight against desertification, with a series of events including the World Economic Forum’s Special Meeting and COP16 focused on tackling the issue.

When we think of deserts, regions such as the Middle East, Northern Africa or Central Asia may spring to mind. But growing desertification in the wake of climate change is increasingly drawing ever wider circles across the globe, increasing steadily . United Nations’ latest data, as presented by 126 Parties in their 2022 national reports, show that 15.5% of land is now degraded, an increase of 4% in as many years.

But this could become a seminal year for the fight against desertification, with two major events scheduled for 2024 in Saudi Arabia to mobilize support. Tackling this growing problem will be a major focus at the World Economic Forum’s forthcoming Special Meeting on Global Collaboration, Growth and Energy for Development in May, and the16th session of the Conference of the Parties to the UN Convention to Combat Desertification (UNCCD) COP16 in December.

The UNCCD is one of the three Rio Conventions, along with the UN Framework Convention on Climate Change and the Convention on Biological Diversity.

What does desertification mean for our planet and people, and how can we mitigate against it?

Have you read?

These start-ups are helping to make life in the sahel more sustainable, why investing in land is a business imperative for a sustainable future, women's land rights: a key to combating desertification and drought, what is desertification and what causes it.

Desertification is a type of land degradation in which an already relatively dry land area becomes increasingly arid , degrading productive soil and losing its bodies of water, biodiversity and vegetation cover.

It is driven by a combination of factors, including climate change, deforestation, overgrazing and unsustainable agricultural practices .

The issue reaches far beyond deserts like the Sahara, Kalahari or Gobi deserts. The UNCCD says that 100 million hectares of productive land are degraded each year . Droughts are becoming more common, and three-quarters of people are expected to face water scarcity by 2050.

Currently, around 2 billion people live in drylands, which are most prone to desertification , according to Earth.org.

Among the most affected regions are Africa and Eastern and Central Asia.

Who is most affected by desertification?

In Africa, some 40 million people are living in severe drought conditions already , according to the World Economic Forum report Quantifying the Impact of Climate Change on Human Health 2024.

And, in Asia, China, Uzbekistan, and Kyrgyzstan are among the countries that have seen temperatures soaring, according to Earth.org. While some of these areas had been classed as having a desert climate since the 1980s, desertification has continued, leading to hotter, wetter climates. In the mountains, a lack of snow has led to the gradual disappearance of glaciers, threatening water security that affects both people and agriculture.

Biodiversity loss and climate change are occurring at unprecedented rates, threatening humanity’s very survival. Nature is in crisis, but there is hope. Investing in nature can not only increase our resilience to socioeconomic and environmental shocks, but it can help societies thrive.

There is strong recognition within the Forum that the future must be net-zero and nature-positive. The Nature Action Agenda initiative, within the Centre for Nature and Climate , is an inclusive, multistakeholder movement catalysing economic action to halt biodiversity loss by 2030.

The Nature Action Agenda is enabling business and policy action by:

Building a knowledge base to make a compelling economic and business case for safeguarding nature, showcasing solutions and bolstering research through the publication of the New Nature Economy Reports and impactful communications.

Catalysing leadership for nature-positive transitions through multi-stakeholder communities such as Champions for Nature that takes a leading role in shaping the net-zero, nature-positive agenda on the global stage.

Scaling up solutions in priority socio-economic systems through BiodiverCities by 2030 , turning cities into engines of nature-positive development; Financing for Nature , unlocking financial resources through innovative mechanisms such as high-integrity Biodiversity Credits Market ; and Sector Transitions to Nature Positive , accelerating sector-specific priority actions to reduce impacts and unlock opportunities.

Supporting an enabling environment by ensuring implementation of the Kunming-Montreal Global Biodiversity Framework and mobilizing business voices calling for ambitious policy actions in collaboration with Business for Nature .

But land degradation also affects more temperate regions. In the US, nearly 40% of the lower 48 states are facing drought, the Forum’s report says, quoting statistics from the US National Integrated Drought Information System.

Southern Europe has seen some of its worst droughts in recent years. In Spain, desertification and overexploitation have severely affected what’s known as “Europe’s kitchen garden”. The European Union has flagged the vulnerability of its southern members to desertification in recent years, pointing not only to Spain but also Portugal, Italy, Greece, Cyprus, Bulgaria and Romania.

What are the impacts of desertification?

According to the UNCCD, around 500 million people live in desertified areas .

They can experience exacerbated poverty, lack of food security and poor health due to malnutrition and lack of access to clean water. They are also more vulnerable to climate change and extreme weather such as droughts and natural disasters. With their livelihoods at stake and a greater risk of conflict over declining resources , they may also face forced migration.

One of the most prominent examples of desertification is the Aralkum desert in central Asia. In the 1960s, the area was covered by the fourth-largest lake in the world, the Aral Sea. Since then, it has shrunk to a tenth of its former size, with only three small, highly salty lakes remaining. In Soviet times, its waters were used for irrigating a semi-desert region to grow cotton, leading to a drop in water levels. Climate change added further impetus to this over time, turning the dry seabed into a salt-covered desert, leaving fishing boats stranded, rusting and livelihoods destroyed.

How can we mitigate against desertification?

There are a wide variety of approaches to address desertification , with many programmes underway around the globe.

Reforestation and afforestation can help revive degraded soil. In Uzbekistan, a regreening programme has planted trees and shrubs across one million hectares along the Aral desert. This includes the black saxual shrub, which is highly drought resistant and can fix salt and sand, stopping it from being swept up and carried inland by sandstorms.

In the Sahel and Sahara region in Africa, the “Great Green Wall” – launched in 2007 by the African Union – aims to restore plant life across 100 million hectares of degraded land. Involving 22 African countries, this initiative will revive the land, store more than 220 million tonnes of carbon and create 10 million jobs by 2030.

Another big part of tackling land degradation is introducing sustainable land management practices, ranging from agroforestry to sustainable grazing and can also improve crop yields and livelihoods.

Water management practices such as rainwater harvesting, drip-water irrigation and planting drought-resistant crops can address the impact of water scarcity.

Other remedial steps include re-vegetation and restoring natural habitats such as wetlands or entire river beds.

The World Economic Forum’s Special Meeting in Saudi Arabia will see a series of announcements and sessions on the topic of desertification, including support for Saudi Arabia as the host of COP16 and joint work between the Forum and Saudi Arabia to compile a programme for December’s event.

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Desertification

Charney's hypothesis

There is a controversy about the advance of deserts in the world (1). There is a widespread belief that the Sahara desert is advancing into the Sahel region, for instance. The Sahel is a narrow band of West Africa between 15 -18 ° N, between the Sahara to the north and savannah (grass and open forest) and equatorial forest to the south. It extends from Senegal at the coast at about 15 ° W, across Mali and Niger, to about 15 ° E. It receives rainfall during a short but active wet season, from late June to mid September. It is covered by grassland and supports a pasture-based society which traditionally moved meridionally following the rains. Its northern limit may be defined by the 200 mm/a isohyet.

Is the Sahara extending into the Sahel? And if so, is this because of fluctuations of rainfall (total amount, rainfall intensity, duration of wet season, …) or is it largely the result of human activities, such as overgrazing or the removal of trees for firewood? There are also the questions: Do deserts create droughts? Do droughts create deserts? In other words, is there a positive climate feedback, which accelerates land degradation? A now classic paper by Jules Charney in 1975 (2) speculated that overgrazing in the Sahel leads to less vegetation, which raises the ground’s albedo, so that less solar radiation is absorbed and the Earth’s surface becomes cooler. It should be noted that the atmosphere above the Sahara experiences continues radiative cooling, because the dry air, free of clouds, absorbs very little of the longwave radiation upwelling from the ground. This radiative cooling is naturally compensated by subsidence heating, and the subsidence sustains the dry air, cloudlessness, and arid surface conditions. According Charney, overgrazing would enhance the radiative loss, which would foster subsidence within the troposphere, leading to drier conditions in the Sahel, and therefore less plant growth during the wet season. Less vegetation means a higher albedo. So we have positive feedback and a self-aggravating process, culminating in desertification, a process of land degradation that destroys its productivity. Charney’s hypothesis was supported by experiments with a very simple GCM, in which he changed the surface albedo from 20% to 30% (3).

The problem of overgrazing in the Sahel is as acute now as it was in the 1960's, yet there is no clear rainfall trend in the Sahel. The period 1930-'60 was slightly wetter than 1960-'90 in most parts of the Sahel. More significant than any trend is the occurrence of dry and wet periods, each lasting several years. The Sahel enjoyed a notably wet decade in the 1950’s, which was followed by a drought in the 70’s and 80’s (1). However, land productivity was fully recovered around 1990. So Charney's hypothesis cannot be confirmed.

To reject Charney's hypothesis, one needs to examine whether the albedo has really increased in the Sahel. Satellite-estimated albedo of the Sahel between 1983-1988 was about 35% in (dry) January and 31% in (wet) July, a difference of about 4%. The seasonal variation greatly exceeded any overall change during the period. This points to there being no irreversible change towards desert. It is concluded that the formation of desert is not a single self-aggravating process, but is complex, reflecting changes of both climate and human activities. There may be incomplete recovery after a dry period, or changes in the composition of the vegetation.

Desertification trends are evaluated by means of the ‘normalised difference vegetation index’ (NDVI). This index, based on satellite data, quantifies the amount of vegetation (1). It is a figure for the ‘green-ness’ of the surface, the ratio of the measured reflectances of red light (i.e. 0.55-0.68 micron wavelength) and near-infra-red (0.73-1.1) in solar radiation. NDVI is strongly correlated with the biological productivity of an area. In the Sahel there is close agreement of the shifts of NDVI and rainfall boundaries during 1980 - 1995, i.e. the NDVI/rainfall relationship remained about constant. In other words, there was no progressive ‘march’ of desert over more fertile areas, no one-way ratchet effect due to deserts causing droughts.

A question related to the question about deserts causing drought, is that of large lakes inducing rain. Nicholson et al. (1) mentioned proposals to flood the Kalahari desert of Botswana to increase the rainfall regionally. The topic was discussed indirectly in Notes 10.I and 10.J, where reasons are given for expecting no influence of forestation on rainfall, unless done over large areas; even then, the enhanced rainfall is insufficient to support the manmade forest.

A separate effect of desertification, apart from any possible influence on rainfall, is an increase of soil erosion and dust storms (4), as shown in Fig 1 . This shows the close relationship between rainfall and dust.

Fig 1 . The frequency of dust storms at Gao (in the Sahel), compared with annual rainfall anomalies (from (1), after (4)). The anomaly unit is the regionally averaged departure from the long-term mean, divided by the standard deviation. The dust occurrence is expressed in terms of the number of days when there is dust haze.

  References

(1) Nicholson, S.E., C.J. Tucker and M.B. Ba 1998. Desertification, drought and surface vegetation: an example from the West African Sahel. Bull. Amer. Meteor. Soc., 79 , 815-29.

(2) Charney, J.G. 1975. Dynamics of deserts and drought in Sahel. Quart. J. Royal Meteor. Soc, 101 , 193-202.

(3) Xue, Y. and J. Shukla 1993. The influence of land surface properties on Sahel climate. J. Climate, 6 , 2232-45.

(4) N’Tchayi, M.G., J.J. Bertrand and S.E. Nicholson 1997. The diurnal and seasonal cycles of desert dust over Africa north of the equator. J. Appl. Meteor. 36 , 868-82.  

New Research

What Really Turned the Sahara Desert From a Green Oasis Into a Wasteland?

10,000 years ago, this iconic desert was unrecognizable. A new hypothesis suggests that humans may have tipped the balance

Lorraine Boissoneault

When most people imagine an archetypal desert landscape—with its relentless sun, rippling sand and hidden oases—they often picture the Sahara. But 11,000 years ago, what we know today as the world’s largest hot desert would’ve been unrecognizable. The now-dessicated northern strip of Africa was once green and alive, pocked with lakes, rivers, grasslands and even forests. So where did all that water go?

Archaeologist David Wright has an idea: Maybe humans and their goats tipped the balance, kick-starting this dramatic ecological transformation. In a new study in the journal Frontiers in Earth Science , Wright set out to argue that humans could be the answer to a question that has plagued archaeologists and paleoecologists for years.

The Sahara has long been subject to periodic bouts of humidity and aridity. These fluctuations are caused by slight wobbles in the tilt of the Earth’s orbital axis, which in turn changes the angle at which solar radiation penetrates the atmosphere. At repeated intervals throughout Earth’s history , there’s been more energy pouring in from the sun during the West African monsoon season, and during those times—known as African Humid Periods—much more rain comes down over north Africa.

With more rain, the region gets more greenery and rivers and lakes. All this has been known for decades. But between 8,000 and 4,500 years ago, something strange happened: The transition from humid to dry happened far more rapidly in some areas than could be explained by the orbital precession alone, resulting in the Sahara Desert as we know it today. “Scientists usually call it ‘poor parameterization’ of the data,” Wright said by email. “Which is to say that we have no idea what we’re missing here—but something’s wrong.”

As Wright pored the archaeological and environmental data (mostly sediment cores and pollen records, all dated to the same time period), he noticed what seemed like a pattern. Wherever the archaeological record showed the presence of “pastoralists”—humans with their domesticated animals—there was a corresponding change in the types and variety of plants. It was as if, every time humans and their goats and cattle hopscotched across the grasslands, they had turned everything to scrub and desert in their wake.

Wright thinks this is exactly what happened. “By overgrazing the grasses, they were reducing the amount of atmospheric moisture—plants give off moisture, which produces clouds—and enhancing albedo,” Wright said. He suggests this may have triggered the end of the humid period more abruptly than can be explained by the orbital changes. These nomadic humans also may have used fire as a land management tool, which would have exacerbated the speed at which the desert took hold.

It’s important to note that the green Sahara always would’ve turned back into a desert even without humans doing anything—that’s just how Earth’s orbit works, says geologist Jessica Tierney, an associate professor of geoscience at the University of Arizona. Moreover, according to Tierney, we don’t necessarily need humans to explain the abruptness of the transition from green to desert.

Instead, the culprits might be regular old vegetation feedbacks and changes in the amount of dust. “At first you have this slow change in the Earth’s orbit,” Tierney explains. “As that’s happening, the West African monsoon is going to get a little bit weaker. Slowly you’ll degrade the landscape, switching from desert to vegetation. And then at some point you pass the tipping point where change accelerates.”

Tierney adds that it’s hard to know what triggered the cascade in the system, because everything is so closely intertwined. During the last humid period, the Sahara was filled with hunter-gatherers. As the orbit slowly changed and less rain fell, humans would have needed to domesticate animals, like cattle and goats , for sustenance. “It could be the climate was pushing people to herd cattle, or the overgrazing practices accelerated denudation [of foliage],” Tierney says. 

Which came first? It’s hard to say with evidence we have now. “The question is: How do we test this hypothesis?” she says. “How do we isolate the climatically driven changes from the role of humans? It’s a bit of a chicken and an egg problem.” Wright, too, cautions that right now we have evidence only for correlation, not causation.

But Tierney is also intrigued by Wright’s research, and agrees with him that much more research needs to be done to answer these questions.

“We need to drill down into the dried-up lake beds that are scattered around the Sahara and look at the pollen and seed data and then match that to the archaeological datasets,” Wright said. “With enough correlations, we may be able to more definitively develop a theory of why the pace of climate change at the end of the AHP doesn’t match orbital timescales and is irregular across northern Africa.”

Tierney suggests researchers could use mathematical models that compare the impact hunter-gatherers would have on the environment versus that of pastoralists herding animals. For such models it would be necessary to have some idea of how many people lived in the Sahara at the time, but Tierney is sure there were more people in the region than there are today, excepting coastal urban areas.

While the shifts between a green Sahara and a desert do constitute a type of climate change, it’s important to understand that the mechanism differs from what we think of as anthropogenic (human-made) climate change today, which is largely driven by rising levels of CO2 and other greenhouse gases. Still, that doesn’t mean these studies can’t help us understand the impact humans are having on the environment now.

“It’s definitely important,” Tierney says. “Understanding the way those feedback (loops) work could improve our ability to predict changes for vulnerable arid and semi-arid regions.”

Wright sees an even broader message in this type of study. “Humans don’t exist in ecological vacuums,” he said. “We are a keystone species and, as such, we make massive impacts on the entire ecological complexion of the Earth. Some of these can be good for us, but some have really threatened the long-term sustainability of the Earth.” 

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Lorraine Boissoneault | | READ MORE

Lorraine Boissoneault is a contributing writer to SmithsonianMag.com covering history and archaeology. She has previously written for The Atlantic, Salon, Nautilus and others. She is also the author of The Last Voyageurs: Retracing La Salle's Journey Across America. Website: http://www.lboissoneault.com/

Sand dunes show the increasing desertification of the Tibetan Plateau, as land dries out and vegetation cover vanishes due to human activity.

• ENVIRONMENT

Desertification, explained

Humans are driving the transformation of drylands into desert on an unprecedented scale around the world, with serious consequences. But there are solutions.

As global temperatures rise and the human population expands, more of the planet is vulnerable to desertification, the permanent degradation of land that was once arable.

While interpretations of the term desertification vary, the concern centers on human-caused land degradation in areas with low or variable rainfall known as drylands: arid, semi-arid, and sub-humid lands . These drylands account for more than 40 percent of the world's terrestrial surface area.

While land degradation has occurred throughout history, the pace has accelerated, reaching 30 to 35 times the historical rate, according to the United Nations . This degradation tends to be driven by a number of factors, including urbanization , mining, farming, and ranching. In the course of these activities, trees and other vegetation are cleared away , animal hooves pound the dirt, and crops deplete nutrients in the soil. Climate change also plays a significant role, increasing the risk of drought .

All of this contributes to soil erosion and an inability for the land to retain water or regrow plants. About 2 billion people live on the drylands that are vulnerable to desertification, which could displace an estimated 50 million people by 2030.

Where is desertification happening, and why?

The risk of desertification is widespread and spans more than 100 countries , hitting some of the poorest and most vulnerable populations the hardest, since subsistence farming is common across many of the affected regions.

More than 75 percent of Earth's land area is already degraded, according to the European Commission's World Atlas of Desertification , and more than 90 percent could become degraded by 2050. The commission's Joint Research Centre found that a total area half of the size of the European Union (1.61 million square miles, or 4.18 million square kilometers) is degraded annually, with Africa and Asia being the most affected.

The drivers of land degradation vary with different locations, and causes often overlap with each other. In the regions of Uzbekistan and Kazakhstan surrounding the Aral Sea , excessive use of water for agricultural irrigation has been a primary culprit in causing the sea to shrink , leaving behind a saline desert. And in Africa's Sahel region , bordered by the Sahara Desert to the north and savannas to the south, population growth has caused an increase in wood harvesting, illegal farming, and land-clearing for housing, among other changes.

The prospect of climate change and warmer average temperatures could amplify these effects. The Mediterranean region would experience a drastic transformation with warming of 2 degrees Celsius, according to one study , with all of southern Spain becoming desert. Another recent study found that the same level of warming would result in "aridification," or drying out, of up to 30 percent of Earth's land surface.

A herder family tends pastures beside a growing desert.

When land becomes desert, its ability to support surrounding populations of people and animals declines sharply. Food often doesn't grow, water can't be collected, and habitats shift. This often produces several human health problems that range from malnutrition, respiratory disease caused by dusty air, and other diseases stemming from a lack of clean water.

Desertification solutions

In 1994, the United Nations established the Convention to Combat Desertification (UNCCD), through which 122 countries have committed to Land Degradation Neutrality targets, similar to the way countries in the climate Paris Agreement have agreed to targets for reducing carbon pollution. These efforts involve working with farmers to safeguard arable land, repairing degraded land, and managing water supplies more effectively.

The UNCCD has also promoted the Great Green Wall Initiative , an effort to restore 386,000 square miles (100 million hectares) across 20 countries in Africa by 2030. A similar effort is underway in northern China , with the government planting trees along the border of the Gobi desert to prevent it from expanding as farming, livestock grazing , and urbanization , along with climate change, removed buffering vegetation.

However, the results for these types of restoration efforts so far have been mixed. One type of mesquite tree planted in East Africa to buffer against desertification has proved to be invasive and problematic . The Great Green Wall initiative in Africa has evolved away from the idea of simply planting trees and toward the idea of " re-greening ," or supporting small farmers in managing land to maximize water harvesting (via stone barriers that decrease water runoff, for example) and nurture natural regrowth of trees and vegetation.

"The absolute number of farmers in these [at-risk rural] regions is so large that even simple and inexpensive interventions can have regional impacts," write the authors of the World Atlas of Desertification, noting that more than 80 percent of the world's farms are managed by individual households, primarily in Africa and Asia. "Smallholders are now seen as part of the solution of land degradation rather than a main problem, which was a prevailing view of the past."

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Savanna Hypothesis, The

• Living reference work entry
• First Online: 01 January 2016
• Cite this living reference work entry

• Gordon H. Orians 4  

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Habitat selection ; Landscape aesthetics

The Savanna Hypothesis states that we retain genetically based preferences for features of high-quality African savannas where our ancestors lived when their brains and bodies evolved into their modern forms.

Introduction

Selection of a place to live is a crucial step in the lives of most animals. Selection depends on the recognition of objects, sounds, and odors to which an animal, molded by natural selection, responds as if it understood their significance for its future survival and reproductive success. Evolutionary theory suggests that the ability of a landscape to evoke positive emotional states should be positively correlated with the expected survival and reproductive success of individuals of that species in it. In other words, good habitats should evoke strong positive responses; poor habitats should evoke weak or negative responses (Orians and Heerwagen 1992 ). Habitat selection has served as a conceptual basis for...

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Orians, G.H. (2016). Savanna Hypothesis, The. In: Weekes-Shackelford, V., Shackelford, T., Weekes-Shackelford, V. (eds) Encyclopedia of Evolutionary Psychological Science. Springer, Cham. https://doi.org/10.1007/978-3-319-16999-6_2930-1

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Claims about desert are familiar and frequent in ordinary non-philosophical conversation. We say that a hard-working student who produces work of high quality deserves a high grade; that a vicious criminal deserves a harsh penalty; that someone who has suffered a series of misfortunes deserves some good luck for a change.

Philosophers have made use of the concept of desert in several contexts. In discussions of the nature of justice, several philosophers have advocated versions of the idea that justice obtains when goods and evils are distributed according to desert. In discussions of the concept of intrinsic value, some philosophers have suggested that happiness may be the greatest good but it has outstanding value only when enjoyed by someone who deserves it. In theories about moral obligation, some consequentialists have defended the idea that right acts lead to outcomes in which higher welfare is preferentially distributed to people who deserve it. In social and political philosophy (or philosophy of law) a number of philosophers have appealed to the concept of desert when discussing the justification of penalties for violations of law.

So appeals to desert appear frequently in many contexts, in philosophy as well as in ordinary non-philosophical talk. Yet many questions remain about desert: how can it be distinguished from mere entitlement? What is its conceptual structure? What kinds of things can be deserving? What kinds of things can be deserved? What kinds of properties can serve as bases on which a deserver deserves a desert? How can claims about desert be justified?

1. Desert and Entitlement

2. deservers, desert, and desert bases, 3. the justification of desert claims, 4. desert and intrinsic value, 5. desertist theories of justice, works cited, other readings, other internet resources, related entries.

It is important here at the outset that we draw attention to a distinction between desert and another concept with which it might be confused. We will speak of this latter concept as the concept of entitlement , though different philosophers use different terminology to mark this distinction.

A typical desert claim is a claim to the effect that someone – the “deserver” – deserves something – the “desert” – in virtue of his or her possession of some feature – the “desert base”. [ 1 ] For example, consider the claim that a certain student deserves a high grade from her teacher in virtue of the fact that she did excellent work in the course. A typical entitlement claim is a claim to the effect that someone is entitled to something from someone on some basis. For example, consider the claim that a customer is entitled to a refund from a merchant in virtue of the fact that the merchandise he purchased from that merchant had been sold with a guarantee and turned out to be defective.

There are obvious structural similarities between desert claims and claims about entitlement. In typical examples of each sort, someone is said to deserve (or be entitled to) something from someone on some basis. However, there is an important difference between the concepts of desert and entitlement. As the terminology is used here, desert is a more purely normative concept, while entitlement is a sociological or empirical concept. If some social or legal institution is in place in your social group, and that institution has a rule that specifies some treatment for those who have some feature, and you have the feature, then you are entitled to that treatment. Thus, for example, suppose that when the customer purchased a certain item, he received a legally binding written guarantee from the seller. The guarantee specified that if the item should turn out to be defective, the seller would either replace the item or refund the money that the buyer had spent for the defective item. In such a case, if the buyer satisfies the conditions stated in the guarantee, and the purchased item is indeed defective, the buyer is entitled to the refund or replacement.

Typical desert claims have a similar structure, but do not always depend in this way on the existence of laws or contracts or other similar social institutions. A person may deserve some sort of treatment even though there are no rules in place in his society that codify the conditions under which someone deserves that sort of treatment. In such a case, a person may deserve something even though he is not entitled to it. Similarly, a person may be entitled to something by some rules that are in place in his society even though he does not deserve it. Some examples may help to make this distinction clearer.

Consider an example involving a wealthy grandfather and two grandchildren. One grandchild is vicious and rich; the other is virtuous and poor. The vicious grandchild never treated his grandfather with respect. The virtuous grandchild was always respectful and caring. Suppose the grandfather leaves his entire fortune to the vicious grandchild. As the terminology is used here, we may want to describe the situation by saying that the vicious grandchild is entitled to the fortune (the rules of the legal system are unambiguous on this point), but at the same time we may want to say that he does not deserve it (he already has too much money; he is a rotten person who never treated his grandfather respectfully). The virtuous grandchild may deserve at least some of the inheritance, but he is not entitled to any of it.

Another example illustrates the same point. Suppose that an athlete has her heart set on doing well in a competition. Suppose she has a lot of natural talent and trains diligently for a long time until she has developed championship-level abilities in her sport. Suppose that the training involves quite a bit of sacrifice on her part. Suppose that at the last minute the competition is cancelled, and the athlete has no opportunity to compete. Then we might say that this was a great misfortune for her; she deserved to have a chance to participate. Unfortunately, there is no rule in the rulebook of the athlete’s sport that says that those who have trained diligently are to get a chance to participate. Let us assume that there is no institution in place in the athlete’s society that specifies that those who train hard shall be given a chance to compete. In this case, it would be wrong to say (using the terminology in the way that has been specified) that the athlete is entitled to a chance to participate, yet we may still feel that she deserved the chance. This seems to be an example of a case in which someone has completely “non-institutional” desert of something.

Some philosophers use the expression ‘pre-institutional desert’ where we use ‘desert’, and ‘institutional desert’ where we use ‘entitlement’. To avoid confusion, we will use ‘desert’ to refer to the relation that does not essentially involve the existence of social or legal institutions, and ‘entitlement’ to refer to the relation that does essentially involve the existence of such institutions. Our focus in this article is on desert; we mention entitlement only as it bears on desert.

In his seminal work on desert and justice (Feinberg 1970) Joel Feinberg presented a catalog of types of seemingly uncontroversial desert claims: a student might deserve a high grade in virtue of having written a good paper; an athlete might deserve a prize in virtue of having excelled in a competition; a successful researcher might deserve an expression of gratitude in virtue of having perfected a disease-preventing serum; a criminal might deserve the contempt of his community in virtue of having committed crimes; the victim of an industrial accident may deserve compensation from his negligent employer; a hard-working public official may deserve to be promoted to a higher office in virtue of her diligence. Leibniz, Kant, and others focused on examples in which a person is said to deserve happiness in virtue of having been morally excellent.

In all these familiar cases, the deserver is a person. But as Feinberg himself mentioned, there does not seem to be any conceptual barrier to saying that non-persons may also be deservers. Thus, for example, it seems acceptable to say that a beautiful ancient city deserves to be preserved; that a unique and formerly vibrant ecosystem deserves to be restored; that the scene of a horrible massacre deserves to be torn down. In moral and political discussions, cases under scrutiny tend to be ones in which deservers are either individual people or groups of people. This should not blind us to the fact that non-persons can also be deservers.

Desert claims also typically involve a desert . This is the thing that the deserver is said to deserve. As Feinberg indicated, familiar deserts include such things as grades, wages, prizes, respect, honors and awards, rights, love, benefits and other such things. Leibniz and Kant would surely insist that we include happiness among the possible deserts; and others would insist that we should mention welfare.

Those deserts may seem at first to be “positive.” However, there are “negative” counterparts. Indeed, some of the items on that list are already negative. Thus, some grades are bad grades, as for example, the F a student might deserve for a very weak paper. Other deserts are uniformly negative: burdens, fines, booby prizes, contempt, dishonors, onerous obligations, penalties, condemnation, hate, etc.

Some contributors to the literature on desert suggest that every desert is either a plus or a minus. Some speak, in this context of “benefits and burdens,” or advantages and disadvantages. However, there are cases in which someone deserves something that is neither good nor bad, neither a benefit nor a burden. Suppose someone who has done outstanding academic work deserves to get an A, while someone who has done completely unsatisfactory work deserves to get an F. It is reasonable to suppose that the A is a good grade – something the recipient will be pleased to get – and the F is a bad grade – something that the recipient will be disappointed to get. But suppose a student did mediocre work and deserves a mediocre grade – a C. This is neither good nor bad, neither a benefit nor a burden. Nevertheless, someone might deserve it. This would be a case in which someone deserves something that is neither “positive” nor “negative.”

The same could be true of welfare. Someone might deserve happiness and (we may assume) that would be a good thing to get; someone else might deserve unhappiness and (we may assume) that would be a bad thing to get. But another person might deserve to be at an intermediate welfare level, neither happy nor unhappy. While it might be good in some way for the person to be at that neutral welfare level, the thing he deserves would be neither good nor bad. So while it is convenient to say that deserts are benefits or burdens – things that will be good or bad for the deserver to receive – in fact some deserts are neither benefits nor burdens.

Feinberg suggested that we can distinguish between “basic” and “derived” deserts. He went on to say that basic deserts are always responsive attitudes such as approval and disapproval. On this view, derived deserts are forms of treatment that would be fitting expressions of the more fundamental basic deserts. Thus, giving a student an A might be the fitting expression for approval of her work; giving a student an F might be the most fitting expression of serious disapproval of her work. Some recent contributors to the literature on desert seem to ignore this distinction between basic and derived desert, but others continue to employ the distinction and to treat it as important. Scanlon, for example, makes it a central feature of his conception of desert (see Scanlon 2013, 2018).

Perhaps the most important and controversial bit of information we typically seek in connection with a claim about desert concerns the desert base . This is generally taken to be the feature in virtue of which the deserver deserves the desert. On this view, a desert base is always a property. If we adopt this view, we will say (for example) that the student deserves a high grade in virtue of her possession of the property of having produced course work of high quality . On another view, a desert base is always a fact. If we adopt this view we will prefer to say that the student deserves her high grade in virtue of the fact that her work was of such high quality .

We are inclined to think that it makes no difference whether we take desert bases to be properties or to be facts. The views seem to be intertranslatable. In this article, simply as a matter of convenience, we generally speak of desert bases as properties.

In some cases there is little debate about whether a certain property serves as a desert base for a certain sort of treatment. This may be illustrated by the example of the student who produced outstanding work in a course and deserves a high grade. Few would debate the claim that the student deserves the grade in virtue of the high quality of her work. The desert base in that case would be having produced academic work of high quality . Similarly consider the case of the cold-blooded criminal who has inflicted great harm on many innocent victims. It is reasonable to suppose that he deserves a harsh penalty in virtue of his evil behavior. In this case, the desert base is something like having inflicted great harm on many innocent victims .

In other cases, however, there would be more controversy about desert bases. A good example involves the desert of wages. Suppose an employee works hard, is productive, is loyal to his employer, and in virtue of some health problems in his family, needs more money. We may agree in such a case that the employee deserves a raise – but we may disagree about the basis on which he deserves that raise.

There is general agreement that properties of certain types cannot serve as desert bases. Consider a case in which punishing an innocent person would have good consequences. The person has this property: being such that punishing him would have good consequences . But it would be seriously counterintuitive to say that the person deserves punishment in virtue of his possession of this property.

Certain general principles about desert bases have been introduced in an effort to explain why certain properties seem ineligible to serve as desert bases. Perhaps the least controversial principle is the so-called “Aboutness Principle,” mentioned by Feinberg. In its propositional form, this principle says that a person can deserve something in virtue of a certain fact only if that fact is a fact “about the person.” In its property form, the principle would say that a person can deserve something in virtue of a certain property only if the person actually has the property. The Aboutness Principle does not offer any assistance with respect to the punishment case just mentioned. After all, the innocent person in that example actually does have the property of being such that punishing him would have good consequences . The fact that punishing him would have good consequences is a fact about him.

Some have said that if someone deserves something, D, in virtue of having some desert base, DB, then the deserving one must be responsible for having DB (see, for example, Rawls 1971; Rachels 1978; Sadurski 1985). This “Responsibility Principle” seems to be satisfied by many of the examples already discussed. The good student, we may suppose, is responsible for having produced good academic work. The cold-blooded criminal, similarly, may seem responsible for his vicious behavior. The hard working employee bears some responsibility for having worked so hard. We may generalize from these cases and conclude that all cases of desert are like this: if someone deserves something, D, on some basis, DB, then he or she is responsible for having DB. Appeal to the Responsibility Principle would explain why the innocent person does not deserve punishment. He is not responsible for having the property of being such that punishing him would have good consequences .

A variety of cases have been offered as counterexamples to the Responsibility Principle. Feldman (1995a) described a case in which patrons at a restaurant became ill as a result of having been served spoiled food. He claimed that the patrons in such a case would deserve compensation. The desert base here seems to be having been harmed by the negligent food preparation by the restaurant – yet the patrons were not responsible for having that desert base. They were innocent victims. A similar thing happens in the case of someone who has been egregiously insulted. She may deserve an apology in virtue of having been insulted, but she is not responsible for the insult. Another case mentioned by McLeod involves a child who, through no fault of his own, comes down with a painful illness. He deserves the care and sympathy of his parents, yet he is not responsible for having become ill.

Others have suggested what may be called “the Temporality Principle”: the idea here is roughly this: if someone deserves something, D, in virtue of having a certain desert base, DB, then he or she must already have DB at the time he or she begins to deserve D (see, for example, Rachels 1978; Kleinig 1971; Sadurski 1985). You cannot deserve something on the basis of a property you will begin to have only later. The Temporality Principle has been invoked in an effort to explain why it is wrong to engage in “pre-punishment.” It is said that even if a certain person is going to commit a crime, he does not begin to deserve punishment for that crime until he actually commits it. This line of thought has been debated. One problem is that even before he commits the crime, the future criminal already has this property: being such that he will later commit a crime . It might be said that he deserves punishment in virtue of already having this property even before he commits the crime. While the Temporality Principle is widely endorsed, counterexamples have been presented (see, for example, Feldman 1995b). Those counterexamples have not been universally accepted (see, for example, Smilansky 1996a, 1996b).

In many cases, when we make a desert claim we mention a distributor . This is the person or institution from whom the deserver deserves to receive the desert. In some cases, the identity of the distributor will be clear. In other cases, it is not so clear. Consider, for example, the motto that the McDonald’s restaurants formerly used: ‘You deserve a break today.’ No distributor is explicitly mentioned in the motto. It just says that you deserve a break. Perhaps when McDonald’s made this statement, they did not have any particular distributor in mind. Maybe they just thought that you deserve it from someone . The same would be true of the Gates Foundation’s former motto according to which ‘Every person deserves the chance to live a healthy and productive life.’ The motto does not mention anyone who has the job of ensuring that everyone gets a chance to live a healthy and productive life. Given that no one has the capacity to ensure that everyone lives a healthy and productive life, we may conclude that in this case no distributor is mentioned precisely because no one is qualified to be a distributor.

In other cases, there is a distributor and its identity is clear. Consider, for example, the claim that a certain elderly professor deserves some respect from his unruly students. Here the distributor is explicitly mentioned: it is the unruly students. Those who endorse the notion that virtuous people deserve happiness in heaven will presumably say that the distributor in that case is God. In social and political contexts we often find philosophers assuming that citizens deserve certain rights from the government of their country.

It may seem that we could relocate this reference to the distributor. We could build reference to the distributor into the description of the desert. Thus, instead of saying that the desert in the example involving the elderly professor is respect , we could say that the desert is respect from his students .

In some cases a desert statement may also indicate something about the strength of the deserver’s desert of the thing deserved. The strength of someone’s desert of something might be indicated loosely, as when we say that someone’s desert of something is “very strong,” or “only slight.” In some cases we can use some numbers to represent strengths of desert, though the choice of a numbering system will be to some extent arbitrary. But there are some important facts here: sometimes you deserve both A and B, but you deserve A more than you deserve B; sometimes two different deservers deserve the same thing and it is not possible for both of them to get it; maybe one of them deserves it more than the other. Sometimes you deserve something, but only to a very slight degree and this desert could easily be overridden by some other consideration.

In many cases a desert statement (if fully spelled out) would also indicate some times . One of these is the time of the deserving; the other is the time when the receipt of the desert is supposed to take place. Thus, for example, suppose a lot of money has been withheld from a certain person’s paycheck each week for a whole year. Suppose in fact the government has withheld more than the person owes in taxes. Then he deserves a refund. Suppose refunds are all given out on April 1. We might want to say this: at every moment in March, the taxpayer deserves to get a refund on April 1. In this example, the time of the deserving is every moment in March . The time at which the deserver deserves to receive the desert is April 1.

A number of related questions have been discussed under the general title of ‘the justification of desert claims.’ Some apparently take the question about justification to be a question about epistemic justification (see, for example, McLeod 1995, 89). If we understand the question in this way, we may want to know how – if at all – a person can be epistemically justified in believing that (for example) hard work is a desert base for reward. Others take the question about justification in a different way. They take it to be a question about explanation . Consider again the question about the justification of the claim that hard work makes us deserve reward. On this second interpretation, the question is: what explains the fact that hard work is a desert base for reward? Others speak in this context of “normative force” (see, for example, Sher 1987, xi). They seem to be concerned with a question about what explains the fact that when someone deserves something, it is obligatory for others to provide it, or good that it be provided. Still others may phrase the question by appeal to concepts of grounding or foundation . They may ask what grounds the fact that those who work hard deserve rewards. Still others write a bit more vaguely about the analysis of desert claims (see, for example, Feinberg 1970).

There is a further distinction to be noted. Some who write about the justification of desert claims seem to think that it is specific desert claims about particular individuals that call for justification. Thus, they might ask for a justification of the claim that Jones deserves a $100 bonus for having worked extra hard over the holiday weekend. Others apparently think that what calls for justification is a more general claim about desert bases and deserts. They might ask for a justification of the claim that hard work is a desert base for financial reward .

We will formulate the discussion in the admittedly vague idiom of justification of claims about desert bases and deserts . But as we understand the question, it can be explicated in this way: suppose someone claims that in general the possession of some desert base, DB, makes people deserve a certain desert, D. If challenged, how could the maker of such a claim support his claim? How could he argue for his assertion? What facts about DB and D could he cite in order to show that he was right – the possession of DB does make someone deserve D?

Some who write on this topic are “monists” about justification; they apparently assume that there is a single feature that will serve in all cases to justify desert claims. Others are “pluralists.” They defend the idea that desert claims fall into different categories, and that each category has its own distinctive sort of justification (see, for example, Feinberg 1970, Sher 1987, and Lamont 1994). We first consider some monist views.

Some popular views about the justification of desert claims are based on the idea that such claims can be justified by appeal to considerations about the values of consequences. Sidgwick seems to be thinking of something like this in The Methods of Ethics where he mentions ‘the utilitarian interpretation of Desert.’ He describes this by saying: ‘when a man is said to deserve reward for any services to society, the meaning is that it is expedient to reward him, in order that he and others may be induced to render similar services by the expectation of similar rewards’ (1907, 284, note 1). (It is not clear that Sidgwick means to defend this view about desert; he seems to be offering it as an account of what a determinist would have to say.)

Sidgwick’s statement has direct implications only for cases in which what is deserved is some sort of reward and the desert base of this desert is some sort of ‘service to society.’ As a result, it is not clear that this idea about justification, taken simply by itself, has any direct relevance to cases in which someone deserves punishment, or compensation, or a prize for outstanding performance, or a grade for academic work.

According to a natural extension of the view that Sidgwick mentioned, a claim to the effect that someone deserves something, D, in virtue of his possession of some feature, DB, is justified by pointing out that giving the person D in virtue of his possession of DB would have high utility.

While there surely are some cases in which giving someone what he deserves would have high utility, this link between desert and utility is just as frequently absent. To see this, consider a case in which a very popular person has engaged in some bad behavior for which he deserves punishment – but suppose in addition that no one believes he is guilty. If he were punished for having done the nasty deed, there would be an outpouring of anger from all of the popular person’s fans and friends who think he has been framed. If our interest were in producing an outcome with high utility, we would have to refrain from punishing him. But in spite of that, since in fact he did do the nasty deed, he does deserve the punishment.

In other cases, giving a person some benefit might have good results even though the person does not deserve to receive those benefits. To see this, imagine that a crazed maniac threatens to murder a dozen hostages unless he is given a half-hour of prime time TV to air his grievances. Giving him this airtime might have high utility – it might be the best thing for those in charge to do in the circumstances – but at the same time we might feel that the maniac does not deserve it.

Another serious problem with the consequentialist approach is brought out by consideration of the famous telishment case, also known as ‘The Small Southern Town.’ The example was presented by Carritt in his Ethical and Political Thinking , but gained great notoriety as a result of being quoted at length in Rawls’s ‘Two Concepts of Rules’ (Rawls 1955). Here is the passage from Carritt:

…if some kind of very cruel crime becomes common, and none of the criminals can be caught, it might be highly expedient, as an example, to hang an innocent man, if a charge against him could be so framed that he were universally thought guilty… (Carritt 1947, 65)

In this example, punishing an innocent person has high utility because it would have great deterrent effect. But the victim of the punishment does not deserve punishment – after all, he is innocent. This highlights an important fact about desert and utility: sometimes it can be expedient to give someone a reward or a punishment that he or she does not deserve.

It appears then that the consequentialist approach confronts overwhelming objections. Sometimes deserved treatment is expedient; sometimes it is not. Sometimes undeserved treatment is expedient; sometimes it is not. As a result, appeals to the utility of giving someone some benefit or burden cannot justify the claim that the person deserves that sort of treatment.

A second approach to the justification of desert claims is based on some ideas concerning institutions. There are several different ways in which this “institutional justification” can be developed. (Our discussion in this section has benefited enormously from McLeod 1999b.)

First, some background: an institution may be identified by a system of rules that define positions, moves, penalties, rewards, etc. In some cases the rules of an institution are carefully written down and perhaps made a matter of legislation. The system of taxation in some country might be a good example. In other cases the rules of an institution are not explicitly formalized. An example might be the system of etiquette governing the writing, sending, replying to, etc. of wedding invitations. It is not easy to say what makes an institution “exist” in a society. That is a puzzle best left to the sociologists.

We may also need to assume that when people set up institutions, they do so with some intention. They are trying to achieve something; or more likely, they are trying to achieve several different things. Maybe different people have different aims. We can say – somewhat vaguely – that the point of an institution is the main goal or aim that people have in establishing or maintaining that institution.

A person may be governed by some institution even if he does not like it, or does not endorse it. Thus, for example, suppose a criminal justice system exists in a certain state. Suppose some miscreant lives in that state and has been charged with some crime. Suppose he is found guilty in a duly established court of law and is sentenced to ten years in prison. He is governed by the rules of the judicial system whether he likes it or not. To be governed by an institution one must live (or perhaps be a visitor) in the state or society where the institution exists, and one must somehow “fall under” the rules. Those rules must “apply to” the individual. Again, these are tricky sociological notions, not easily spelled out.

Some philosophers have said things that suggest that it is possible to justify a desert claim by identifying a currently existing, actual institution according to which the deserver is entitled to the desert. We can state this idea a bit more clearly:

AID: The claim that a person, S, deserves something, D, on the basis of the fact that he has a feature, DB, is justifiable if and only if there is some social institution, I; I exists in S’s society; S is governed by I; according to the rules of I, those who have DB are to receive D; S has DB.

This “actual institutional” account of desert is almost universally rejected. [ 2 ] There are several independent sources of difficulty. Most of these emerge from the requirement that a desert claim is justifiable always and only when there is an appropriate actual social institution. This produces a number of devastating objections. Suppose a thoroughly decent person has suffered a number of serious misfortunes. He deserves a change of luck; he deserves some good luck for a change. Suppose he lives in a country where there is no social institution that supplies compensatory benefits to those who have had bad luck. If AID were true, it would be impossible to justify the claim that he deserves it.

An equally serious objection arises from the fact that some of the institutions that actually exist are morally indefensible. Let us imagine a thoroughly horrible social institution – slavery. Suppose some unfortunate individual is governed by that institution. Suppose the institution contains rules that say that slaves who are strong and healthy shall be required to work without pay in the cotton fields. Suppose this individual is strong and healthy. Consider the claim that he deserves to be required to work in the fields without pay in virtue of the fact that he is strong and healthy. AID implies that this desert claim is justified. That is as preposterous as it is offensive.

The general point: we must not lose sight of the fundamental difference between entitlement and desert . AID seems to confuse these. It seems to say that you deserve something if and only if you are entitled to it by the rules of an actual institution. Since there are bad institutions, and cases in which desert arises in the absence of institutions, this is clearly a mistake.

We can deal with all of these objections by altering the institutional account of justification. Instead of making the justification of a desert claim depend upon the existence of an actual social institution, we can make it depend upon the rules that would be contained in some ideal social institution. The main change is that we no longer require that the social institution exists. We require instead that it be an ideal institution – an institution that would be in some way excellent or preferable. Then we can attempt to justify desert claims by saying that the deservers would be entitled to those deserts by the rules of an ideal social institution.

We can state the thesis this way:

IID: The claim that a person, S, deserves something, D, on the basis of the fact that he has a feature, DB, is justifiable if and only if there is some possible social institution, I; I would be ideal for S’s society; S would be governed by I; according to the rules of I, those who have DB are to receive D; S has DB.

Before we can evaluate this proposal, we have to explain in greater detail what makes a possible institution “ideal” for a society. We might try to define ideality by saying that an ideal institution is one that would distribute benefits and burdens to people precisely in accord with their deserts. With this account of ideality in place, IID generates quite a few correct results. Unfortunately, it would be unhelpful in the present context. After all, the aim here is to explain how desert claims can be justified. This account would explain desert by appeal to ideal institutions, and then explain ideal institutions by appeal to desert.

Following the rule utilitarians, we could attempt to define ideality by saying that a possible institution is ideal for a society if and only if having it as the society’s institutional way of achieving its point would produce more utility than would the having of any alternative institution. This yields a form of the institutional approach that seems importantly similar to the consequentialist approach already discussed.

Unfortunately, with this conception of ideality in place, the proposal seems to inherit some of the defects of the simpler consequentialist approach. It implies, for example, that if it is possible for there to be a seriously unfair but nevertheless utility maximizing institution, then people would deserve the burdens allocated to them by the rules of that institution, even if it were not in place.

A further difficulty arises in connection with actual but not optimific institutions. Suppose, for example, the utility maximizing ice-skating institution would have rules specifying that in order to win the gold medal, a competitor must perform a 7 minute free program; a 6 minute program of required figures; and that all contestants must wear regulation team uniforms consisting of full length trousers and matching long-sleeved team shirts. Suppose in fact that this institution is not in place in Nancy’s society. Suppose instead that the de facto institution contains some slightly different but still fairly reasonable rules for ice-skating competitions. Suppose Nancy abides by all the relevant extant rules and is declared the winner in a competition. She is entitled to the gold medal by the actual rules. It may seem, in such a case, that her claim to deserve the medal would be justified. But since she would not be entitled to it by the rules of the ideal institution, IID implies that it is impossible to justify her claim that she deserves the medal by virtue of her performance here tonight.

It appears, then, that difficulties confront the attempt to justify desert claims by appeal to claims about the entitlements created by institutions, actual or ideal.

Some philosophers have drawn attention to alleged connections between desert claims and facts about “appraising attitudes” or “responsive attitudes” (see, for example, Feinberg 1970). Commentators have understood these philosophers to have been defending the idea that desert claims can be justified by appeal to facts about appraising attitudes. Some have said, for example, that David Miller defended a view of this sort in his Social Justice (1976). While there may be debate about whether Miller actually intended to be defending such a view, it is worthwhile to consider it. (In the discussion that follows we are indebted to McLeod 1995 and McLeod 2013.)

We need first to understand what is meant by ‘appraising attitude.’

Admiration, approval, and gratitude are typically cited as examples of “positive” appraising attitudes. In each case, if a person has such an attitude toward someone, he has that attitude in virtue of some feature that he takes the person to have. Suppose, for example, that you admire someone; then you must admire her for something she is or something she did . Maybe she worked hard; or wrote a good paper; or can run very fast; or is able to play the violin beautifully. Similarly for the other positive appraising attitudes.

Disapproval, resentment, contempt, “thinking ill of,” and condemnation may be cited as examples of “negative” appraising attitudes. They are similar to the positive attitudes in this respect, if you disapprove of someone, then you must disapprove of him for something he is or something he did . Maybe he plagiarized a paper; maybe he is totally out of shape; maybe he is utterly talentless.

Miller says that if we did not have these attitudes, ‘we would not and could not use the concept of desert’ (1976, 89). He also says that the range of possible desert bases coincides with the range of bases for appraising attitudes. You cannot deserve something on the basis of your possession of a property, DB, unless we could have an appraising attitude toward you on the basis of your possession of DB. But what is most important for our present purposes is that, according to Miller, ‘the existence of these appraising attitudes makes intelligible the connection between a desert judgment and its basis’ (89). Some have understood Miller to be claiming that something about these appraising attitudes provides the answer to our question about the justification of desert claims.

A certain appraising attitude may seem appropriate to a desert claim. For example, suppose a person feels strong approval (a positive appraising attitude) of a subject in virtue of his heroic action. The attitude would be appropriate to the claim that the hero deserves a reward for his heroism. On the other hand, if someone feels contempt (a negative appraising attitude) for a person in virtue of his cowardice, then this attitude would be appropriate to the claim that the coward deserves some sort of penalty. On one possible view, whether a desert judgment is justifiable depends upon whether the person who makes that judgment has an appraising attitude that is appropriate to the desert claim.

This view (presumably not Miller’s) is clearly confused. Suppose the leader of a terrorist gang claims that a member of his gang deserves respect for having set off a suicide bomb in an elementary school. Suppose the leader has great admiration for this the gang member precisely because he set off the bomb. On the current proposal, since the leader in fact has a positive appraising attitude toward the member, his desert claim is justified. That cannot be right.

The difficulty cannot be resolved by appealing to the reactions of the community. It is easy enough to imagine a case in which the overwhelming majority of the bomber’s community admire him for destroying the elementary school. Surely, however, no matter how many of his compatriots admire him for doing this deed, the claim that he deserves admiration for having done it is still not justified.

Instead of appealing to facts about the appraising attitudes that others in fact have, we might consider a different question: what sort of appraising attitude would be fitting for others to have in virtue of the fact that he has committed this deed? If it would be fitting for others to admire him for bombing the school, then he deserves admiration. If it would be fitting for others to hold him in contempt for bombing the school, then he deserves contempt.

In general, then, we might say that the claim that S deserves a certain benefit (burden) in virtue of having done X is justified if and only if it would be fitting for observers to have a positive (negative) appraising attitude toward S in virtue of his having done X.

This proposal seems misguided for several reasons. First, it seems to be circular. It purports to explain the justification of desert claims by appeal to claims about what appraising attitude would be “fitting.” But to say that it would be fitting for someone to receive a certain benefit is dangerously close to saying that he deserves to receive it. In this form the proposal seems circular.

Furthermore, it appears that there are cases in which a person deserves something but in which no appraising attitude seems to be fitting. Suppose, for example, that an abandoned child is in need of medical care and nurturance. The fact that the child is sick does not make it appropriate for onlookers to admire her or to condemn her. It does not call for any “positive” or “negative” appraising attitude. Nevertheless, the claim that the child deserves medical care and nurturance in virtue of her need might be justified. This objection presents a genuine difficulty only if every appraising attitude is a favorable or an unfavorable attitude. If we assume that pity, or compassion, is also an appraising attitude, the problem mentioned here will not arise.

In his (1970) Feinberg hints at a different way in which appraising attitudes might figure in the justification of desert claims. Feinberg starts by noting that ‘reasonable men naturally entertain certain responsive attitudes toward various actions, qualities, and achievements.’ Those who engage in the actions or manifest the qualities thereby deserve to be the subjects of the responsive attitudes. Going further, we can say that various forms of treatment – punishments, rewards, prizes, etc. – are the customary way of expressing the natural responsive attitudes. When such forms of treatment are in this way the customary and natural ways of expressing the attitudes, then those who engage in the action or manifest the quality deserve, in a derived way, to receive the treatment. The suggestion, then, is that in such cases the claim that someone deserves D on the basis of his possession of DB can be justified by pointing out that giving D is the conventional way of expressing the responsive attitude that reasonable men entertain toward those with DB.

If understood in the suggested way, this account would rely on some problematic assumptions about the responsive attitudes that ‘reasonable men naturally entertain.’ We might well doubt whether all such men invariably entertain those attitudes in cases where the recipients deserve to be their subject. In any case where only some reasonable men entertain the attitudes, it would be impossible to justify the associated desert claims. On the other hand, if we required merely that some reasonable men entertain the attitudes in question, then it would become far too easy to justify dubious desert claims. Furthermore, it would make it possible for there to be cases in which someone both deserves a certain treatment and also deserves not to get that treatment.

The details of the appraising attitudes approach remain controversial.

A few philosophers – including George Sher (1987) and Julian Lamont (1994) – said things that suggest a pluralistic approach to the question about the justification of desert claims. On this view, there are several different “external values”; different values would be relevant in different cases; different desert claims would be justifiable by appeal to different external values. Thus, for example, consider the claim that you deserve a reward for having saved a life. The external value in this case might be some combination of the value of courage and the alleged value of human life. Consider a different case in which someone claims that you deserve a high grade for having done outstanding work in a course. In this case, the external value might be the value of academic achievement. In every case, a desert claim – if it can be justified at all – can be justified by pointing out that giving the deserver the desert would properly respect the associated external value. A full exposition of this approach would require a detailed account of what makes a certain external value be relevant to a desert claim; it would also require a detailed account of what is meant by saying that some action would “properly respect” some external value.

Here is a natural and appealing idea: it is a good thing when people get what they deserve. If I am distributing raises, and only Jones deserves a raise, then it would be better for me to give the raise to Jones than to anyone else.

As simple and straightforward as this idea is, given certain background assumptions it raises difficult questions about the connection between desert and “goodness,” or intrinsic value.

Some consequentialist moral theories make use of (and so presuppose the intelligibility of) the notion of the “intrinsic value of a state of affairs,” or the “intrinsic value of a possible world.” This notion of intrinsic value is a quantitative one: consequentialists usually assume that we can choose a unit for measuring intrinsic value, and in terms of that unit we can say that the intrinsic value of one possible world is 100 units, while the intrinsic value of another is, say, merely 10 units.

Common forms of consequentialism go on to say that whether an action A is permissible or impermissible is determined by how the intrinsic value of the world that would be actual if A were performed compares to the intrinsic values of the worlds that would be actual if the alternatives to A were performed instead. (The alternatives to A are the actions other than A that are “open” to the agent at the time he performs A.) One standard form of consequentialism says that an act A is permissible if and only if none of the worlds that would be actual were the agent to perform one of the alternatives to A has a greater intrinsic value than the world that would be actual were he to perform A. Thus, in a consequentialist framework, if one holds that facts about desert make a difference to intrinsic value, one may also hold that facts about desert make a difference to whether an act is permissible or impermissible. If, in virtue of the fact that only Jones deserves a raise, it is better to give a raise only to Jones, then the right thing to do is to give the raise only to Jones.

This section started with the generalization that, other things being equal, it is a good thing when people get what they deserve. We have just seen that in a consequentialist framework this generalization about value leads naturally to another one, about moral obligation: other things being equal, one ought to ensure that people get what they deserve. But one might endorse the second generalization without the first. Some opponents of consequentialism hold that talk of “the intrinsic value of a possible world” makes no sense (for example, Thomson 2008). They could still accept that, other things being equal, one ought to ensure that people get what they deserve. One could hold, for example, that the obligation to ensure that people get what they deserve is a prima facie duty, in the sense that W. D. Ross (2002) attaches to this phrase.

Some consequentialists have hoped that basing their theory of obligation on a “desert-sensitive” theory of intrinsic value will make their theory immune to certain common objections. To get a sense of what these philosophers hope to accomplish we will need a more detailed statement of a theory of intrinsic value. We will make use of the notion of individual welfare, or well-being. Talk of someone’s well-being is talk of how good their life is for them. We may speak of how good someone’s life is at a particular moment, or how good their life is as a whole; our focus here is on welfare-values of entire lives. Let us assume, as is common in discussions of desert, that welfare is a quantitative notion. We can choose a unit for measuring welfare; then for each person there is, relative to that choice of unit, a number that represents how good that person’s life is for them. One simple (non-desert-sensitive) theory of intrinsic value for possible worlds says that the (number representing) the intrinsic value of a world is equal to the sum of the numbers representing the “welfare values” of the lives of the people in that world.

According to standard consequentialism, combined with this theory of intrinsic value, “distribution does not matter.” All that matters, for determining whether an act is right, is the sum total of the welfare in the world that would be actual if that act were performed, and how that sum total differs from the totals in the worlds that would be actual if some alternative act were performed; it does not matter how good any particular individual’s life is. John Rawls famously argued that this is an objectionable feature of the theory (Rawls 1971, 26; his target is a slightly different theory of intrinsic value).

A desert-adjusted theory of intrinsic value might yield a version of standard consequentialism that evades this objection. If worlds in which people get what they deserve are better than worlds in which people do not, then it is not true that distribution does not matter. A desert-adjusted theory of intrinsic value could say that, if Smith and Jones each deserves 25 units of welfare, then a world in which they each receive 25 units is better than a world in which Smith receives 50 and Jones receives 0.

Feldman (1995a, 567) is explicit that the goal of his desert-sensitive version of consequentialism is to respond to Rawls’ objection. He suggests that his theory can handle many of the examples commonly thought to raise problems for consequentialism, such as the Organ Transplant. In another paper Feldman suggests that a desert-adjusted theory of intrinsic value can avoid Parfit’s Repugnant Conclusion (see Feldman 1995c; for the Repugnant Conclusion, see Parfit 1984; for reservations about Feldman’s response to Rawls’ objection, and an alternative, see McLeod 2006).

What might a desert-adjusted theory of intrinsic value, one that might form the basis for a desert-sensitive version of consequentialism, look like? To evaluate desert-adjusted theories of intrinsic value we need to see them stated at a greater level of detail than we have seen so far. Presumably, if it is a good thing when people get what they deserve, then if the people in world w 1 are closer to getting what they deserve than the people in world w 2 , w 1 is better (has a greater intrinsic value) than w 2 (other things being equal). But, again, intrinsic value is a quantitative notion. So it makes sense to ask: how much better is w 1 than w 2 ? 10 units? 100 units? Even if we say a lot more about what worlds w 1 and w 2 are like, the answers to these questions are not obvious.

To make a start let us go back to an assumption we quietly made three paragraphs back: that welfare levels are among the things that people deserve. This claim does not seem controversial. It follows from the common idea that the wicked deserve to suffer, and the saintly deserve to prosper, for to prosper is to have a relatively high welfare level. But philosophers who attempt to formulate (welfarist) desert-sensitive theories of intrinsic value often make a stronger assumption: that when it comes to determining the intrinsic value of a possible world, all that matters is the extent to which people get the welfare levels they deserve. Suppose I deserve an apology from my neighbor in virtue of the fact that he (inadvertently) tore up some of the plants in my yard. But suppose also that I do not really care about my yard, or about the quality of my relationship with my neighbor. Getting the apology would mean nothing to me, nor would I be upset if my neighbor did not apologize. The apology would not make my life better or worse. Then on the stronger assumption, the intrinsic value of the world is not higher if I get the apology than if I don’t – even though only if I get the apology do I get something I deserve.

One possible justification for this assumption goes as follows. Even though we may deserve all sorts of things, only instances of someone’s deserving a certain welfare level are instances of “moral desert.” And only moral desert “matters” for the intrinsic value of a possible world. A theory that says the world is no better if I get that apology is not false-but-legitimately-oversimplified. It is saying the truth. According to this line of thought, it is not, in fact, always better when people get what they deserve. It is only better if they get what they morally deserve. (Shelly Kagan focuses on moral desert, presumably to the exclusion of other kinds of desert, in chapter 1 of his 2012.)

Justified or not, most work on desert-sensitive theories of intrinsic value does assume that the only instances of desert that matter are instances of deserved welfare. What should a desert-sensitive theory of intrinsic value that makes this assumption look like? If the value of a possible world is a function, not just of the welfare levels of the people in that world, but also of the welfare levels they deserve, just which function is it?

Producing a theory that answers this question and is initially plausible is not easy. One way to approach the problem is to start with another simplifying assumption. The simple non-desert-sensitive theory of intrinsic value stated above is “totalist”; the intrinsic value of a possible world is got by summing up “contributions” made by each individual “separately.” The amount of intrinsic value contributed by an individual is equal to (or proportional to) that person’s welfare level. We could try for a desert-sensitive theory that is also totalist. The contribution made by an individual will not (or not always) be equal to their welfare level; the amount they deserve will also be relevant. Still, the value of the world as a whole will just be the sum of the individual contributions.

Here is a sketch of a theory like this. It treats someone’s desert level as a “multiplier.” The value an individual contributes to the intrinsic value of a possible world is equal to the product of the welfare level they receive in that world and the welfare level they deserve. (A more sophisticated treatment of the idea of “desert-as-multiplier” may be found in Kagan 2012, section 2.4.)

This theory says plausible things about simple cases. If Smith deserves 10 units of welfare and Jones deserves 20, and you can either ensure that Smith receives 10 units, or that Jones receives 10 units, the theory says that it is better to ensure that Jones receives the 10 units. For if Smith receives the welfare, the total value of the world will be equal to 100, while if Jones does, the total value will be equal to 200. These facts are summarized in the table below (the multiplications in the contribution columns are “welfare level times desert level”):

The idea behind using deserved welfare levels as multipliers is that the welfare of more deserving people is worth more than that of less deserving people. As far as the quality of the lives of the individuals involved are concerned, 10 units of welfare is 10 units of welfare, no matter who it “goes to”: if Smith’s life is made better by 10 units of welfare, his life is made better by the same amount as if Jones’ life is made better by 10 units. But as far as the world is concerned, it does make a difference who the 10 units goes to. When 10 units of welfare goes to someone highly deserving, someone who deserves a high welfare level, the value of that 10 units is “augmented,” so that 10 units of welfare corresponds to a much larger number of units of value-for-the-world.

While the desert-as-multiplier idea gets some cases right, it gets other cases very wrong. Think again of Smith and Jones, deserving 10 and 20 units of welfare, respectively. Suppose that, if you do nothing, Jones will live a life worth 100 units, and Smith will live a life worth 0 units. Your only two options are to act so that Jones lives a life worth 110 and Smith “stays where he would have been” (he lives a life worth 0), or act so that Jones stays where he would have been, and Smith lives a life worth 10. The table below shows the values of the worlds that correspond to each of your options, according to this theory:

The theory says you should augment Jones. This is implausible. Even if you do nothing, Jones will be living a life far better than the one he deserves to be living. What sense is there in making his life better, when instead you could cause Smith to be living a life he deserves, rather than one worse than he deserves? [ 3 ]

It seems wrong to multiply every bit of welfare Jones receives by 20, even bits of welfare that put him way above the level of welfare he deserves, when computing his contribution to the intrinsic value of the world. This failure of the desert-as-multiplier view suggests an alternative mathematical role for deserved welfare levels. What is important is not the welfare level you deserve, but how close you are to the welfare level you deserve: how good the “fit” is between what you get and what you deserve. A natural way to measure fit is to look at the distance between what you get and what you deserve: the absolute value of the difference between your welfare level and your deserved welfare level. (So when Jones deserves 20 units and gets 100, his “fit value” is the number 80.)

Having latched on to the importance of fit values, how should we make use to them? The simplest way to implement the idea that ‘the closer one is to getting what one deserves, the better’ defines the contribution made to intrinsic value by an individual as follows:

Contribution = welfare level − fit value.

The minus sign is there because someone’s fit value goes up as their welfare level gets farther away from their deserved welfare level. Thus increases in the fit value correspond to worse states of affairs; so we want fit values to make a negative impact on contributions.

This new theory gives a plausible judgment about our second Smith/Jones case. Here are the values it assigns:

Philosophers have articulated other principles they think a desert-sensitive theory of value should entail, and have proposed yet more complicated “contribution formulas” as parts of theories of that sort. For example, Eric Carlson holds that if you have a bunch of people with the same desert level, and you “have a fixed amount of welfare to distribute between them” (really, in each world that you can “make actual” the sum of their welfare levels is the same), then the world in which they all receive the same welfare level should have the greatest intrinsic value. Equal levels of welfare are best, when everyone is equally deserving. The theory we just described is incompatible with this idea. (For Carlson’s theory, which does entail this principle, see Carlson 1997. Feldman 1995a articulated many ideas about how intrinsic values should be adjusted to take desert into account. Persson 1997 distinguished the idea of desert as a multiplier (he called it the “merit idea”) from the idea that what matters is the fit between desert and receipt; he sees both ideas at work in Feldman’s paper. Other constraints people have wanted to place on a desert-sensitive theory may be found in Carlson 1997, Arrhenius 2006, and Skow 2012.)

The theories we have discussed so far aim to be “overall” theories of intrinsic value, theories of intrinsic value all things considered, even if they may make some simplifying assumptions about what is valuable. Another approach to theorizing about desert aims to do something different. Shelly Kagan, in his book The Geometry of Desert (2012), aims at a theory of “intrinsic value from the perspective of desert.” To have a complete theory of intrinsic value one would have to take Kagan’s theory and find a way to combine it with theories of value from other perspectives.

Kagan’s book is by far the most comprehensive discussion of the role of desert in the theory of value. He discusses both “noncomparative desert” and “comparative desert.” Without trying to be too precise about this distinction, comparative desert concerns how the fit between one person’s welfare level and desert level compares to that of others; noncomparative desert ignores these comparisons. His theory of noncomparative desert comprises several claims, the core of which are these:

It is best, from the perspective of noncomparative desert, when someone gets exactly the welfare level they deserve. (That is, a world in which he gets exactly what he deserves is better than a world in which he gets more or less, other things being equal.)

If someone has a positive desert level, then it is better, from the perspective of noncomparative desert, if they get more than they deserve, than if they get less (by the same amount); moreover, the degree to which it is better to get more than one deserves increases as one’s desert level increases. The opposite is true if someone has a negative desert level.

The image below illustrates these claims. Each “mountain” plots an individual’s value, from the perspective of non-comparative desert, as a function of their welfare level. The “peak” of a person’s mountain sits directly above the welfare level that person (non-comparatively) deserves; this illustrates claim 1, that things are best when someone gets they welfare level they deserve. Note also that the mountain on the left-hand side of the y-axis has a steeper eastern slope than western slope. This illustrates part of claim 2. It indicates that if you could either overcompensate a person who deserves a negative amount of welfare, or undercompensate him, by the same amount, it is better to undercompensate him. The mountain on the right-hand side of the y-axis illustrates the corresponding claim about someone with “positive desert”: it is better to overcompensate than to undercompensate such a person. The image also illustrates a claim that Kagan calls “Bell Motion” (this claim is also part of 2): the mountains “swing” in a counter-clockwise direction, as they move from left to right in the diagram. Mountains farther to the right have shallower eastern slopes and steeper western slopes. This means, among other things, that if you have to overcompensate one person by a fixed amount, it is best to overcompensate the person with the highest desert level. Overcompensating makes things worse from the perspective of non-comparative desert; overcompensating the most deserving person is, however, less bad, brings about a smaller vertical drop in the graph, than overcompensating anyone else would.

So far we have been discussing Kagan’s theory of non-comparative desert. His theory of comparative desert is meant to answer questions like the following: suppose that there are two people, that one of them is getting more welfare than he deserves, and that there is nothing we can do about that. What must the welfare level of the other person be, if the demands of comparative desert are to be perfectly satisfied? Kagan advocates what he calls the “Y-gap” view. The image below illustrates this view. Suppose that the mountain on the left represents the person whose welfare level we cannot control, and the mountain on the right represents the person whose welfare level we can control. Then we should overcompensate the person on the right by that amount which results in his Y-gap being the same as that of the person on the left. A person’s Y-gap is the vertical distance between the peak of his mountain, and his actual location (in this case) on the eastern slope. The vertical bars in the diagram depict the two Y-gaps. In this case, although the person on the left is over-compensated by amount A, the person on the right must be over-compensated by a greater amount B, to achieve the same Y-gap, and so to perfectly satisfy the demands of comparative desert, as Kagan sees them.

One question about Kagan’s theory is, what exactly are we measuring when we measure intrinsic value from the perspective of desert? In his book Kagan remains agnostic about whether it is better if a more deserving person gets exactly what he deserves than if a less deserving person does. Maybe this is better; but maybe, on the other hand, a situation in which someone who deserves a high welfare level gets exactly what he deserves is just as good as a situation in which someone who deserves a low (but still positive) welfare gets exactly what he deserves (2012, section 4.3). However, on one natural understanding of the perspective of desert, there is not much room for debate here. It is natural to think that ‘from the perspective of desert,…’ just means ‘taking into account only how close people are to getting what they deserve,…’ If this is right then it is obvious that a situation in which someone who deserves a welfare level of 50 and gets a welfare level of 50 is just as good, from the perspective of desert, as a situation in which someone who deserves a welfare level of 200 gets a welfare level of 200. (One who held this view can, of course, say that in another sense the second situation is better: it is better all-things-considered, because the total amount of welfare in that situation is higher.) The fact that Kagan does not think it obvious that the two situations are equally good from the perspective of desert is evidence that he rejects this account of what the perspective of desert is. (For more on this question about Kagan’s theory, see Appendix I of Feldman 2003, and Skow 2014.)

There is a long tradition according to which justice is fundamentally a matter of receipt in accord with desert. There are passages in the writings of Aristotle, Leibniz, Mill, Sidgwick, Ross and others in which this idea seems to be present. [ 4 ] The abstract desertist idea can be combined with different views about what people deserve and the bases upon which they deserve these things; for each combination of these views about deserts and desert bases, there is a different version of the desertist theory of justice. One of the broadest of these may be called “Universal Desertism about Justice.” It is the idea that justice obtains when people receive everything they deserve on any basis. Although Mill did not accept this conception of justice, he claimed that something quite like it is very widely accepted by “the general mind.” Mill said:

It is universally considered just that each person should obtain that (whether good or evil) which he deserves ; and unjust that he should obtain a good, or be made to undergo an evil, which he does not deserve. This is, perhaps, the clearest and most emphatic form in which the idea of justice is conceived by the general mind ( Utilitarianism , ch 5, para 7). [ 5 ]

When combined with natural and popular assumptions about what people deserve, Universal Desertism gives an account of a form of justice that probably would not be of much interest to social and political philosophers. For given these assumptions about what people deserve, the view implies that in order for there to be perfect justice in a society, every student would have to get every grade that he or she deserves, and every athlete would have to win every competition that he or she deserves to win, every neighbor would have to receive every apology and thank-you note that he or she deserves, and everyone would have to receive the amount of respect, and admiration, and love, and contempt, and good luck that he or she deserves. The society would be a veritable wonderland of requited desert in which no one would have any grounds for complaint about being short-changed about anything. Surely, however, when political philosophers are drawn to the idea that justice is a matter of receipt in accord with desert, they do not have anything quite so fantastic in mind.

Leibniz maintained a desertist theory of justice that makes use of considerably restricted views about the relevant desert and desert bases. He described what he called ‘the law of justice’ in these words:

… everyone is to participate in the perfection of the universe, and to have personal happiness, in proportion to his own virtue and to the extent that his will has contributed to the common good. (Leibniz 1697)

Leibniz evidently was imagining a view according to which there is only one main currency of justice (‘happiness and participation in the perfection of the universe’), and only one main desert base (‘virtue and the extent to which his will has contributed to the common good’) whose magnitude determines the amount of the desert he deserves. Leibniz suggested that it falls to God to ensure that people receive these deserts in the afterlife.

We can say that “Divine Moral Desertism” is the view that justice obtains when everyone receives from God in the afterlife precisely the level of happiness or unhappiness that he or she deserves on the basis of his or her level of moral virtue or vice during life.

Clearly it is possible for there to be a situation in which the level of justice as measured by Universal Desertism is very low, but the level of justice as measured by Divine Moral Desertism is very high. This would happen if people rarely received the prizes and awards and income and other things that they deserve here on earth, but if in addition they always received their heavenly rewards from God in the afterlife.

It is also possible for there to be a situation in which the level of justice as measured by Universal Desertism is very high, but the level of justice as measured by Divine Moral Desertism is very low. This would happen if people often received the apologies, thank-you notes, wages, grades, honorific jobs, etc. that they deserve on earth, but if in addition they never received any heavenly or infernal rewards in an afterlife for the virtue or vice that they manifested while they lived.

While Divine Moral Desertism might be of interest to some theologians or philosophers of religion, it is doubtful that any social or political philosopher would have any professional interest in it. Social and political philosophers are more interested in earthly justice – the kind of justice that obtains in virtue of things that governments are called upon to do for their citizens here on earth. But Divine Moral Desertism concerns things that God does; and benefits or burdens to be received in the afterlife, rather than on earth.

A historically important form of desertism emerges if we continue to maintain that the relevant desert bases are all manifestations of moral virtue and vice, but we introduce different assumptions about deserts and distributors. Instead of saying (with Leibniz) that the relevant deserts are levels of happiness and unhappiness to be experienced in heaven or hell, we can say that the relevant deserts are levels of happiness and unhappiness to be experienced here on earth, during our lives. Furthermore, instead of saying that the distributor from whom we deserve to receive these rewards is God, we can say that we deserve them from our country. The result is a form of desertism according to which there is perfect justice in a country if and only if in every case in which a citizen of that country deserves to be at a certain level of happiness or unhappiness in virtue of having lived at a certain level of moral virtue or vice, the government of his or her country sees to it that the person comes to be at that level of happiness during his or her lifetime. We can call this “Earthly Moral Desertism about Justice.”

It should be obvious that justice as measured by Earthly Moral Desertism is not equivalent to justice as measured by Divine Moral Desertism.

In several passages in A Theory of Justice John Rawls attacks what he takes to be the desertist conception of justice. In these passages, Rawls seems to have in mind something quite like Earthly Moral Desertism. He mentions what he takes to be the motto of desertism: ‘justice is happiness according to virtue’ (1971, 310). Some of his objections to desertism turn on difficulties that governments would face if they were to try to ensure a proper fit between citizens’ levels of virtue and happiness. This indicates that Rawls was imagining (and trying to refute) a form of desertism that would saddle the government with the task of matching happiness levels to virtue levels.

A more plausible form of earthly desertism might attempt to assess states or communities for the way in which economic items such as money, jobs, and taxes, and political items such as political rights and opportunities and obligations are distributed. The imagined form of desertism could purport to give an account of the circumstances under which these things have been distributed justly even though it is silent on the distribution of other very important things such as happiness, or victories in sporting events, or warm loving relationships or apologies.

Instead of focusing on all the things that anyone could deserve, or upon just one thing – happiness – such a theory could focus on what we may call ‘political economic deserts.’ These might include such things as political rights and obligations, other benefits and burdens we get from our countries, security of certain sorts, access to publicly owned or regulated infrastructure such as transportation systems, educational systems, judicial systems, communication systems, etc.

Instead of focusing on all the desert bases in virtue of which anyone could deserve anything, or simply upon the single desert base of moral virtue, a theory of political economic justice could focus on what we may call ‘political economic desert bases.’ These might include such things as being a citizen; having been unjustifiably harmed by a government agency; having earned a lot of money; being keen on getting into business; being vulnerable to robbers and muggers who might attack. The theory could thus focus on desert bases such that it is the business of a government to take note of the fact that its citizens manifest these bases, and it is the business of that government to try to see to it that its citizens receive the things that they deserve on these bases.

Furthermore, the imagined theory could focus on what we may call our ‘political economic distributors.’ In the typical case, the political economic distributor for a certain person is the government of that person’s country, or suitable representatives of that government. The resulting theory, which we may dub ‘Political Economic Desertism about Justice,’ then could maintain that there is perfect political economic distributive justice in a country if and only if in every case in which a citizen of that country deserves a political economic desert in virtue of having a political economic desert base, the government of his or her country ensures that he or she receives that desert.

It should be clear that there might be perfect justice as measured by Political Economic Desertism in some country even though some citizens of that country fail to get some of the things they deserve. Maybe the citizens are getting everything they deserve from their country, but some fail to receive the apologies that they deserve from their spouses and children, and others fail to receive the good luck in sports or romance that they deserve. Indeed, there could be perfect justice as measured by Political Economic Desertism in every country in some possible world even though many residents of that world fail to receive lots of things that they deserve.

It should also be clear that there is no interesting connection between justice as measured by Divine Moral Desertism and justice as measured by this Political Economic Desertism. We can easily imagine a situation in which people receive all the political economic deserts that they deserve from their governments, but never receive any of the heavenly rewards they deserve in the afterlife.

Suppose the government in some country steadfastly keeps out of the business of tracking the levels of virtue in its citizens. Suppose this government also steadfastly keeps out of the business of worrying about how happy its citizens are. But suppose in addition that the government scrupulously distributes income tax refunds, in-state tuition waivers, voting rights, police protection, and other such things to citizens who deserve to have them. Then the level of justice as measured by Earthly Moral Desertism in that country could be very low, but the level of justice as measured by Political Economic Desertism would be very high. So these are clearly distinct concepts of justice.

In recent work, after explicating his concept of desert, T. M. Scanlon presents an extended argument designed to show “not just that the particular conception of desert that [he has] examined … plays no role in distributive justice. It is rather that initially plausible claims that individuals deserve certain economic benefits turn out, on closer examination, either to be invalid or to reduce to claims of justice of some other identifiable sort” (see Scanlon 2013, 2018). Scanlon’s claim seems to be that no fundamentally desertist theory of distributive justice is correct.

In an effort to explicate the notion of desert that he has in mind, Scanlon points out some principles concerning it that he means to endorse. First he distinguishes between desert and entitlement and reminds the reader that the mere fact that someone is entitled to a certain form of treatment by the rules of some institution is not sufficient by itself to show that he or she deserves that treatment. This would be evident in cases in which the entitlement-generating institution is itself seriously unjust. Next, Scanlon reminds the reader that the fact that some treatment would have good consequences is not, in itself, a basis for saying that the person deserves that treatment. Scanlon also accepts the notion that there is a distinction between basic and derived desert. If a person deserves a form of treatment, then this desert must be related to a more fundamental form of desert involving reactive attitudes. The deserved treatment must be a standard way of expressing the deeper fact that the person deserves the attitude. In general, Scanlon accepts the idea that if a person deserves some treatment, the basis on which he or she deserves it must involve his or her own behavior or character. In virtue of the fact that Scanlon endorses all these familiar doctrines about desert, it seems fair to say that his concept of desert is entirely within the mainstream.

Scanlon sketches several proposed desert bases by appeal to which a desertist might attempt to explain why justice requires that citizens receive economic benefits from their countries. These include (a) being morally meritorious, (b) having expended effort in productive labor, (c) having made some other socially valuable contribution, and (d) being in possession of some special talent. In each case, Scanlon claims either that the alleged factor is not a desert base at all, or else that appeal to it cannot explain why certain people deserve greater economic benefits from their countries.

The central problem that Scanlon emphasizes is that, as he sees it, desertist theories of justice cannot explain how it can be just for different citizens to receive different-sized benefits from their countries. In this context, he hints at a two-level view according to which citizens may be entitled to different-sized benefits by the rules and regulations of some distributive institution that has been established in their country. Scanlon seems to acknowledge that if the institution itself is just, the citizens will deserve the different-sized benefits to which they are entitled. But he emphasizes that this desert of differential benefits will arise only if the institution that authorizes them is itself somehow justified. Scanlon suggests that such institutions may be justified, and so the scheme as a whole may be on the right track, but he seems to claim that the justification of the institution would then have to appeal to some justifying feature other than desert. And so, as he sees it, the scheme as a whole would not be a desertist theory of distributive justice.

However, a defender of a desertist theory of political economic distributive justice like the one sketched earlier might claim, in reply, that the distributional system itself might be justified in virtue of the fact that citizens deserve to live in a country where such a system is in place. Perhaps it could be argued that citizens deserve this because they need it in order to flourish as human beings, and no individual human being is capable of establishing such a distributional system on his or her own. If this is right, it would apparently follow that the theory as a whole is a desertist theory of distributive justice. It remains to be seen whether Scanlon’s objections to desertist theories of justice ultimately succeed, or whether a desertist theory of the sort sketched may in the end prove to be acceptable.

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How to cite this entry . Preview the PDF version of this entry at the Friends of the SEP Society . Look up topics and thinkers related to this entry at the Internet Philosophy Ontology Project (InPhO). Enhanced bibliography for this entry at PhilPapers , with links to its database.

• McLeod, O., “Desert”, Stanford Encyclopedia of Philosophy (Winter 2013 Edition), Edward N. Zalta (ed.), URL = < https://plato.stanford.edu/archives/win2013/entries/desert/ >. [This is the previous entry on Desert in the Stanford Encyclopedia of Philosophy — see the version history .]
• Bibliography on Desert , at philpapers.org.

consequentialism | justice: distributive | justice: retributive | value: intrinsic vs. extrinsic | well-being

Acknowledgments

The authors would like to thank Oxford University Press for allowing them to re-use some material that appears in Fred Feldman, Distributive Justice: Getting What We Deserve from our Country .

Copyright © 2020 by Fred Feldman < ffeldman @ philos . umass . edu > Brad Skow < bskow @ mit . edu >

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What Is A Research (Scientific) Hypothesis? A plain-language explainer + examples

By:  Derek Jansen (MBA)  | Reviewed By: Dr Eunice Rautenbach | June 2020

If you’re new to the world of research, or it’s your first time writing a dissertation or thesis, you’re probably noticing that the words “research hypothesis” and “scientific hypothesis” are used quite a bit, and you’re wondering what they mean in a research context .

“Hypothesis” is one of those words that people use loosely, thinking they understand what it means. However, it has a very specific meaning within academic research. So, it’s important to understand the exact meaning before you start hypothesizing. 

Research Hypothesis 101

• What is a hypothesis ?
• What is a research hypothesis (scientific hypothesis)?
• Requirements for a research hypothesis
• Definition of a research hypothesis
• The null hypothesis

What is a hypothesis?

Let’s start with the general definition of a hypothesis (not a research hypothesis or scientific hypothesis), according to the Cambridge Dictionary:

Hypothesis: an idea or explanation for something that is based on known facts but has not yet been proved.

In other words, it’s a statement that provides an explanation for why or how something works, based on facts (or some reasonable assumptions), but that has not yet been specifically tested . For example, a hypothesis might look something like this:

Hypothesis: sleep impacts academic performance.

This statement predicts that academic performance will be influenced by the amount and/or quality of sleep a student engages in – sounds reasonable, right? It’s based on reasonable assumptions , underpinned by what we currently know about sleep and health (from the existing literature). So, loosely speaking, we could call it a hypothesis, at least by the dictionary definition.

But that’s not good enough…

Unfortunately, that’s not quite sophisticated enough to describe a research hypothesis (also sometimes called a scientific hypothesis), and it wouldn’t be acceptable in a dissertation, thesis or research paper . In the world of academic research, a statement needs a few more criteria to constitute a true research hypothesis .

What is a research hypothesis?

A research hypothesis (also called a scientific hypothesis) is a statement about the expected outcome of a study (for example, a dissertation or thesis). To constitute a quality hypothesis, the statement needs to have three attributes – specificity , clarity and testability .

Let’s take a look at these more closely.

Need a helping hand?

Hypothesis Essential #1: Specificity & Clarity

A good research hypothesis needs to be extremely clear and articulate about both what’ s being assessed (who or what variables are involved ) and the expected outcome (for example, a difference between groups, a relationship between variables, etc.).

Let’s stick with our sleepy students example and look at how this statement could be more specific and clear.

Hypothesis: Students who sleep at least 8 hours per night will, on average, achieve higher grades in standardised tests than students who sleep less than 8 hours a night.

As you can see, the statement is very specific as it identifies the variables involved (sleep hours and test grades), the parties involved (two groups of students), as well as the predicted relationship type (a positive relationship). There’s no ambiguity or uncertainty about who or what is involved in the statement, and the expected outcome is clear.

Contrast that to the original hypothesis we looked at – “Sleep impacts academic performance” – and you can see the difference. “Sleep” and “academic performance” are both comparatively vague , and there’s no indication of what the expected relationship direction is (more sleep or less sleep). As you can see, specificity and clarity are key.

Hypothesis Essential #2: Testability (Provability)

A statement must be testable to qualify as a research hypothesis. In other words, there needs to be a way to prove (or disprove) the statement. If it’s not testable, it’s not a hypothesis – simple as that.

For example, consider the hypothesis we mentioned earlier:

Hypothesis: Students who sleep at least 8 hours per night will, on average, achieve higher grades in standardised tests than students who sleep less than 8 hours a night.  

We could test this statement by undertaking a quantitative study involving two groups of students, one that gets 8 or more hours of sleep per night for a fixed period, and one that gets less. We could then compare the standardised test results for both groups to see if there’s a statistically significant difference. 

Again, if you compare this to the original hypothesis we looked at – “Sleep impacts academic performance” – you can see that it would be quite difficult to test that statement, primarily because it isn’t specific enough. How much sleep? By who? What type of academic performance?

So, remember the mantra – if you can’t test it, it’s not a hypothesis 🙂

Defining A Research Hypothesis

You’re still with us? Great! Let’s recap and pin down a clear definition of a hypothesis.

A research hypothesis (or scientific hypothesis) is a statement about an expected relationship between variables, or explanation of an occurrence, that is clear, specific and testable.

So, when you write up hypotheses for your dissertation or thesis, make sure that they meet all these criteria. If you do, you’ll not only have rock-solid hypotheses but you’ll also ensure a clear focus for your entire research project.

What about the null hypothesis?

You may have also heard the terms null hypothesis , alternative hypothesis, or H-zero thrown around. At a simple level, the null hypothesis is the counter-proposal to the original hypothesis.

For example, if the hypothesis predicts that there is a relationship between two variables (for example, sleep and academic performance), the null hypothesis would predict that there is no relationship between those variables.

At a more technical level, the null hypothesis proposes that no statistical significance exists in a set of given observations and that any differences are due to chance alone.

And there you have it – hypotheses in a nutshell. 

If you have any questions, be sure to leave a comment below and we’ll do our best to help you. If you need hands-on help developing and testing your hypotheses, consider our private coaching service , where we hold your hand through the research journey.

Psst... there’s more!

This post was based on one of our popular Research Bootcamps . If you're working on a research project, you'll definitely want to check this out ...

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16 Comments

Very useful information. I benefit more from getting more information in this regard.

Very great insight,educative and informative. Please give meet deep critics on many research data of public international Law like human rights, environment, natural resources, law of the sea etc

In a book I read a distinction is made between null, research, and alternative hypothesis. As far as I understand, alternative and research hypotheses are the same. Can you please elaborate? Best Afshin

This is a self explanatory, easy going site. I will recommend this to my friends and colleagues.

Very good definition. How can I cite your definition in my thesis? Thank you. Is nul hypothesis compulsory in a research?

It’s a counter-proposal to be proven as a rejection

Please what is the difference between alternate hypothesis and research hypothesis?

It is a very good explanation. However, it limits hypotheses to statistically tasteable ideas. What about for qualitative researches or other researches that involve quantitative data that don’t need statistical tests?

In qualitative research, one typically uses propositions, not hypotheses.

could you please elaborate it more

I’ve benefited greatly from these notes, thank you.

This is very helpful

well articulated ideas are presented here, thank you for being reliable sources of information

Excellent. Thanks for being clear and sound about the research methodology and hypothesis (quantitative research)

I have only a simple question regarding the null hypothesis. – Is the null hypothesis (Ho) known as the reversible hypothesis of the alternative hypothesis (H1? – How to test it in academic research?

this is very important note help me much more

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By Clifford D. Simak , first published in Astounding Science Fiction .

When a space exploration program costs five men their lives, the manager of the program decides to send himself and his dog to Jupiter to investigate the men’s disappearances and save Earth from an encroaching apocalypse.

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Kent Fowler manages a program that sends men to Jupiter. The men are converted to Lopers, a type of lifeform that can withstand the pressure of Jupiter’s atmosphere. They are being sent there to investigate how to prevent Jupiter’s pressure from drawing in the Earth and destroying mankind. The problem is, Fowler has sent five men over there, and none of them have come back. Feeling pressure from his colleagues, Fowler decides to send himself and his dog, Towser, to Jupiter. They are both converted into Lopers, and now Towser can speak. He quickly tells Fowler the formula needed to prevent the encroaching apocalypse. They wander Jupiter, discussing their time together, and they realize that, despite having solved the mystery, they don’t want to go back to Earth. Instead, they decide to remain Lopers on Jupiter.

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Definition of hypothesis

Did you know.

The Difference Between Hypothesis and Theory

A hypothesis is an assumption, an idea that is proposed for the sake of argument so that it can be tested to see if it might be true.

In the scientific method, the hypothesis is constructed before any applicable research has been done, apart from a basic background review. You ask a question, read up on what has been studied before, and then form a hypothesis.

A hypothesis is usually tentative; it's an assumption or suggestion made strictly for the objective of being tested.

A theory , in contrast, is a principle that has been formed as an attempt to explain things that have already been substantiated by data. It is used in the names of a number of principles accepted in the scientific community, such as the Big Bang Theory . Because of the rigors of experimentation and control, it is understood to be more likely to be true than a hypothesis is.

In non-scientific use, however, hypothesis and theory are often used interchangeably to mean simply an idea, speculation, or hunch, with theory being the more common choice.

Since this casual use does away with the distinctions upheld by the scientific community, hypothesis and theory are prone to being wrongly interpreted even when they are encountered in scientific contexts—or at least, contexts that allude to scientific study without making the critical distinction that scientists employ when weighing hypotheses and theories.

The most common occurrence is when theory is interpreted—and sometimes even gleefully seized upon—to mean something having less truth value than other scientific principles. (The word law applies to principles so firmly established that they are almost never questioned, such as the law of gravity.)

This mistake is one of projection: since we use theory in general to mean something lightly speculated, then it's implied that scientists must be talking about the same level of uncertainty when they use theory to refer to their well-tested and reasoned principles.

The distinction has come to the forefront particularly on occasions when the content of science curricula in schools has been challenged—notably, when a school board in Georgia put stickers on textbooks stating that evolution was "a theory, not a fact, regarding the origin of living things." As Kenneth R. Miller, a cell biologist at Brown University, has said , a theory "doesn’t mean a hunch or a guess. A theory is a system of explanations that ties together a whole bunch of facts. It not only explains those facts, but predicts what you ought to find from other observations and experiments.”

While theories are never completely infallible, they form the basis of scientific reasoning because, as Miller said "to the best of our ability, we’ve tested them, and they’ve held up."

• proposition
• supposition

hypothesis , theory , law mean a formula derived by inference from scientific data that explains a principle operating in nature.

hypothesis implies insufficient evidence to provide more than a tentative explanation.

theory implies a greater range of evidence and greater likelihood of truth.

law implies a statement of order and relation in nature that has been found to be invariable under the same conditions.

Examples of hypothesis in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'hypothesis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Greek, from hypotithenai to put under, suppose, from hypo- + tithenai to put — more at do

1641, in the meaning defined at sense 1a

Phrases Containing hypothesis

• counter - hypothesis
• nebular hypothesis
• null hypothesis
• planetesimal hypothesis
• Whorfian hypothesis

Articles Related to hypothesis

This is the Difference Between a...

This is the Difference Between a Hypothesis and a Theory

In scientific reasoning, they're two completely different things

Dictionary Entries Near hypothesis

hypothermia

hypothesize

Cite this Entry

“Hypothesis.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/hypothesis. Accessed 28 Apr. 2024.

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Hypothesis is a testable statement that explains what is happening or observed. It proposes the relation between the various participating variables. Hypothesis is also called Theory, Thesis, Guess, Assumption, or Suggestion. Hypothesis creates a structure that guides the search for knowledge.

In this article, we will learn what is hypothesis, its characteristics, types, and examples. We will also learn how hypothesis helps in scientific research.

What is Hypothesis?

A hypothesis is a suggested idea or plan that has little proof, meant to lead to more study. It’s mainly a smart guess or suggested answer to a problem that can be checked through study and trial. In science work, we make guesses called hypotheses to try and figure out what will happen in tests or watching. These are not sure things but rather ideas that can be proved or disproved based on real-life proofs. A good theory is clear and can be tested and found wrong if the proof doesn’t support it.

Hypothesis Meaning

A hypothesis is a proposed statement that is testable and is given for something that happens or observed.

• It is made using what we already know and have seen, and it’s the basis for scientific research.
• A clear guess tells us what we think will happen in an experiment or study.
• It’s a testable clue that can be proven true or wrong with real-life facts and checking it out carefully.
• It usually looks like a “if-then” rule, showing the expected cause and effect relationship between what’s being studied.

Characteristics of Hypothesis

Here are some key characteristics of a hypothesis:

• Testable: An idea (hypothesis) should be made so it can be tested and proven true through doing experiments or watching. It should show a clear connection between things.
• Specific: It needs to be easy and on target, talking about a certain part or connection between things in a study.
• Falsifiable: A good guess should be able to show it’s wrong. This means there must be a chance for proof or seeing something that goes against the guess.
• Logical and Rational: It should be based on things we know now or have seen, giving a reasonable reason that fits with what we already know.
• Predictive: A guess often tells what to expect from an experiment or observation. It gives a guide for what someone might see if the guess is right.
• Concise: It should be short and clear, showing the suggested link or explanation simply without extra confusion.
• Grounded in Research: A guess is usually made from before studies, ideas or watching things. It comes from a deep understanding of what is already known in that area.
• Flexible: A guess helps in the research but it needs to change or fix when new information comes up.
• Relevant: It should be related to the question or problem being studied, helping to direct what the research is about.
• Empirical: Hypotheses come from observations and can be tested using methods based on real-world experiences.

Sources of Hypothesis

Hypotheses can come from different places based on what you’re studying and the kind of research. Here are some common sources from which hypotheses may originate:

• Existing Theories: Often, guesses come from well-known science ideas. These ideas may show connections between things or occurrences that scientists can look into more.
• Observation and Experience: Watching something happen or having personal experiences can lead to guesses. We notice odd things or repeat events in everyday life and experiments. This can make us think of guesses called hypotheses.
• Previous Research: Using old studies or discoveries can help come up with new ideas. Scientists might try to expand or question current findings, making guesses that further study old results.
• Literature Review: Looking at books and research in a subject can help make guesses. Noticing missing parts or mismatches in previous studies might make researchers think up guesses to deal with these spots.
• Problem Statement or Research Question: Often, ideas come from questions or problems in the study. Making clear what needs to be looked into can help create ideas that tackle certain parts of the issue.
• Analogies or Comparisons: Making comparisons between similar things or finding connections from related areas can lead to theories. Understanding from other fields could create new guesses in a different situation.
• Hunches and Speculation: Sometimes, scientists might get a gut feeling or make guesses that help create ideas to test. Though these may not have proof at first, they can be a beginning for looking deeper.
• Technology and Innovations: New technology or tools might make guesses by letting us look at things that were hard to study before.
• Personal Interest and Curiosity: People’s curiosity and personal interests in a topic can help create guesses. Scientists could make guesses based on their own likes or love for a subject.

Types of Hypothesis

Here are some common types of hypotheses:

Simple Hypothesis

Complex hypothesis, directional hypothesis.

• Non-directional Hypothesis

Null Hypothesis (H0)

Alternative hypothesis (h1 or ha), statistical hypothesis, research hypothesis, associative hypothesis, causal hypothesis.

Simple Hypothesis guesses a connection between two things. It says that there is a connection or difference between variables, but it doesn’t tell us which way the relationship goes.

Complex Hypothesis tells us what will happen when more than two things are connected. It looks at how different things interact and may be linked together.

Directional Hypothesis says how one thing is related to another. For example, it guesses that one thing will help or hurt another thing.

Non-Directional Hypothesis

Non-Directional Hypothesis are the one that don’t say how the relationship between things will be. They just say that there is a connection, without telling which way it goes.

Null hypothesis is a statement that says there’s no connection or difference between different things. It implies that any seen impacts are because of luck or random changes in the information.

Alternative Hypothesis is different from the null hypothesis and shows that there’s a big connection or gap between variables. Scientists want to say no to the null hypothesis and choose the alternative one.

Statistical Hypotheis are used in math testing and include making ideas about what groups or bits of them look like. You aim to get information or test certain things using these top-level, common words only.

Research Hypothesis comes from the research question and tells what link is expected between things or factors. It leads the study and chooses where to look more closely.

Associative Hypotheis guesses that there is a link or connection between things without really saying it caused them. It means that when one thing changes, it is connected to another thing changing.

Causal Hypothesis are different from other ideas because they say that one thing causes another. This means there’s a cause and effect relationship between variables involved in the situation. They say that when one thing changes, it directly makes another thing change.

Hypothesis Examples

Following are the examples of hypotheses based on their types:

Simple Hypothesis Example

• Studying more can help you do better on tests.
• Getting more sun makes people have higher amounts of vitamin D.

Complex Hypothesis Example

• How rich you are, how easy it is to get education and healthcare greatly affects the number of years people live.
• A new medicine’s success relies on the amount used, how old a person is who takes it and their genes.

Directional Hypothesis Example

• Drinking more sweet drinks is linked to a higher body weight score.
• Too much stress makes people less productive at work.

Non-directional Hypothesis Example

• Drinking caffeine can affect how well you sleep.
• People often like different kinds of music based on their gender.
• The average test scores of Group A and Group B are not much different.
• There is no connection between using a certain fertilizer and how much it helps crops grow.

Alternative Hypothesis (Ha)

• Patients on Diet A have much different cholesterol levels than those following Diet B.
• Exposure to a certain type of light can change how plants grow compared to normal sunlight.
• The average smarts score of kids in a certain school area is 100.
• The usual time it takes to finish a job using Method A is the same as with Method B.
• Having more kids go to early learning classes helps them do better in school when they get older.
• Using specific ways of talking affects how much customers get involved in marketing activities.
• Regular exercise helps to lower the chances of heart disease.
• Going to school more can help people make more money.
• Playing violent video games makes teens more likely to act aggressively.
• Less clean air directly impacts breathing health in city populations.

Functions of Hypothesis

Hypotheses have many important jobs in the process of scientific research. Here are the key functions of hypotheses:

• Guiding Research: Hypotheses give a clear and exact way for research. They act like guides, showing the predicted connections or results that scientists want to study.
• Formulating Research Questions: Research questions often create guesses. They assist in changing big questions into particular, checkable things. They guide what the study should be focused on.
• Setting Clear Objectives: Hypotheses set the goals of a study by saying what connections between variables should be found. They set the targets that scientists try to reach with their studies.
• Testing Predictions: Theories guess what will happen in experiments or observations. By doing tests in a planned way, scientists can check if what they see matches the guesses made by their ideas.
• Providing Structure: Theories give structure to the study process by arranging thoughts and ideas. They aid scientists in thinking about connections between things and plan experiments to match.
• Focusing Investigations: Hypotheses help scientists focus on certain parts of their study question by clearly saying what they expect links or results to be. This focus makes the study work better.
• Facilitating Communication: Theories help scientists talk to each other effectively. Clearly made guesses help scientists to tell others what they plan, how they will do it and the results expected. This explains things well with colleagues in a wide range of audiences.
• Generating Testable Statements: A good guess can be checked, which means it can be looked at carefully or tested by doing experiments. This feature makes sure that guesses add to the real information used in science knowledge.
• Promoting Objectivity: Guesses give a clear reason for study that helps guide the process while reducing personal bias. They motivate scientists to use facts and data as proofs or disprovals for their proposed answers.
• Driving Scientific Progress: Making, trying out and adjusting ideas is a cycle. Even if a guess is proven right or wrong, the information learned helps to grow knowledge in one specific area.

How Hypothesis help in Scientific Research?

Researchers use hypotheses to put down their thoughts directing how the experiment would take place. Following are the steps that are involved in the scientific method:

• Initiating Investigations: Hypotheses are the beginning of science research. They come from watching, knowing what’s already known or asking questions. This makes scientists make certain explanations that need to be checked with tests.
• Formulating Research Questions: Ideas usually come from bigger questions in study. They help scientists make these questions more exact and testable, guiding the study’s main point.
• Setting Clear Objectives: Hypotheses set the goals of a study by stating what we think will happen between different things. They set the goals that scientists want to reach by doing their studies.
• Designing Experiments and Studies: Assumptions help plan experiments and watchful studies. They assist scientists in knowing what factors to measure, the techniques they will use and gather data for a proposed reason.
• Testing Predictions: Ideas guess what will happen in experiments or observations. By checking these guesses carefully, scientists can see if the seen results match up with what was predicted in each hypothesis.
• Analysis and Interpretation of Data: Hypotheses give us a way to study and make sense of information. Researchers look at what they found and see if it matches the guesses made in their theories. They decide if the proof backs up or disagrees with these suggested reasons why things are happening as expected.
• Encouraging Objectivity: Hypotheses help make things fair by making sure scientists use facts and information to either agree or disagree with their suggested reasons. They lessen personal preferences by needing proof from experience.
• Iterative Process: People either agree or disagree with guesses, but they still help the ongoing process of science. Findings from testing ideas make us ask new questions, improve those ideas and do more tests. It keeps going on in the work of science to keep learning things.

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Summary – Hypothesis

A hypothesis is a testable statement serving as an initial explanation for phenomena, based on observations, theories, or existing knowledge. It acts as a guiding light for scientific research, proposing potential relationships between variables that can be empirically tested through experiments and observations. The hypothesis must be specific, testable, falsifiable, and grounded in prior research or observation, laying out a predictive, if-then scenario that details a cause-and-effect relationship. It originates from various sources including existing theories, observations, previous research, and even personal curiosity, leading to different types, such as simple, complex, directional, non-directional, null, and alternative hypotheses, each serving distinct roles in research methodology. The hypothesis not only guides the research process by shaping objectives and designing experiments but also facilitates objective analysis and interpretation of data, ultimately driving scientific progress through a cycle of testing, validation, and refinement.

FAQs on Hypothesis

What is a hypothesis.

A guess is a possible explanation or forecast that can be checked by doing research and experiments.

What are Components of a Hypothesis?

The components of a Hypothesis are Independent Variable, Dependent Variable, Relationship between Variables, Directionality etc.

What makes a Good Hypothesis?

Testability, Falsifiability, Clarity and Precision, Relevance are some parameters that makes a Good Hypothesis

Can a Hypothesis be Proven True?

You cannot prove conclusively that most hypotheses are true because it’s generally impossible to examine all possible cases for exceptions that would disprove them.

How are Hypotheses Tested?

Hypothesis testing is used to assess the plausibility of a hypothesis by using sample data

Can Hypotheses change during Research?

Yes, you can change or improve your ideas based on new information discovered during the research process.

What is the Role of a Hypothesis in Scientific Research?

Hypotheses are used to support scientific research and bring about advancements in knowledge.

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