Introduction
Philosopher David Hume pointed to a difference between factual claims, which are the objective of science, and value claims which urge action: the is-ought, fact-value distinction. The distinction is essential to science, because otherwise factual claims that upset some people may be suppressed before they can be tested: truth must precede moral judgment. Unfortunately, the is-ought distinction has been increasingly ignored in recent decades.
Corrupting Social Science
Harvard philosopher Hilary Putnam published in 2004 a book with the catchy “this is the last word” title: The Collapse of the Fact/Value Dichotomy. The book and subsequent work by Putnam and others announced the demise of David Hume’s distinction1 without actually disproving it. Putnam’s book was influential. Although his victory was not complete, his enthusiastic critique minimized the distinction. Post-Putnam scholars could happily dismiss uncomfortable findings as “bigoted” or “racist” without worrying about their truth.
The effects of allowing values to intrude on factual judgments have been especially destructive of social science. Sensitive issues can no longer be discussed or are biased in political ways—ways justified by the “unavoidable entanglement” of values and scientific facts. If a finding displeases a politically active group, it will be suppressed. Truth thus canceled, ideology fills the void. In this way much social science has become corrupt.
I begin with the clarity of Hume’s original argument. There are two famous quotes where Hume declares his position, the first from the mature Enquiry and the second from his earlier “fell dead-born from the press” Treatise. The first emphasizes the fact-value distinction, the second the is-ought distinction. Both distinguish between passive fact/isand a compulsion to action value/ought.
When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames: For it can contain nothing but sophistry and illusion.
Where a passion is neither founded on false suppositions, nor chuses means insufficient for the end, the understanding can neither justify nor condemn it. It is not contrary to reason to prefer the destruction of the whole world to the scratching of my finger. It is not contrary to reason for me to chuse my total ruin, to prevent the least uneasiness of an Indian or person wholly unknown to me….
In every system of morality, which I have hitherto met with, I have always remarked, that the author proceeds for some time in the ordinary way of reasoning, and establishes the being of a God, or makes observations concerning human affairs; when of a sudden I am surprized to find, that instead of the usual copulations of propositions, is, and is not, I meet with no proposition that is not connected with an ought, or an ought not. This change is imperceptible; but is, however, of the last consequence. For as this ought, or ought not, expresses some new relation or affirmation, it is necessary that it should be observed and explained; and at the same time that a reason should be given, for what seems altogether inconceivable, how this new relation can be a deduction from others, which are entirely different from it. But as authors do not commonly use this precaution, I shall presume to recommend it to the readers; and am persuaded, that this small attention would subvert all the vulgar systems of morality, and let us see, that the distinction of vice and virtue is not founded merely on the relations of objects, nor is perceived by reason.
The reason that Hume spent no more time on the fact-value distinction than these extracts from two very long disquisitions is not, I submit, because he thought the distinction unimportant but, on the contrary, that he thought it obvious. He was right.
So, how do Putnam and his congeners attempt to blur an obvious distinction? The first thing to notice is that their discussion happened within the context not of physical or biological, but of economic science. Economics deals with the human condition. Economic outcomes affect human happiness. Obviously, their human impact cannot be ignored. Add to this the troubling fact that most economic questions cannot be answered by that mainstay of science, the experimental method.2 Lacking, in most cases, a conclusive method to test and prove its claims, economics is especially vulnerable to emotional intrusions.
In addition to its scientific limitations, economics has the added problem of being a policy science. Economists are often asked to solve real-world problems. Alternatively, economists should provide a theoretical framework that policymakers can consult at their discretion. But they should not provide advice. As Friedrich Hayek commented: “The curious task of economics is to demonstrate to men how little they really know about what they imagine they can design.”3
Not all economists agree. Hence, it was easy for Putnam, Amartya Sen and others to assume that economics must involve moral, value, considerations. Sen argued that economists must openly discuss what counts as well-being, how societies should evaluate social states and, most importantly, how inequality matters. The problem, of course, is not that these topics should not be discussed but that they should form part of the science of economics. It makes more sense for economists to study, for example, the stability and wealth distribution predicted by their models, and leave it to the political process to choose policy based on policymakers’ weighing of different outcomes. Yet Sen’s economics is infused with values that are taken for granted. Not everyone agrees that inequality, per se, should rank high as a policy value, for example, yet Sen and his supporters accept what they call “capability equality” as an axiom. And how can “justice” be part of a scientific account?
The target of Putnam collaborator Vivian Walsh and others were the Humean claims by influential British economist Lionel Robbins. Robbins argued that ethical considerations not only could but should be omitted from economic science.4 In particular, he defended two propositions. First, “feelings” are not part of science: “The assertion that one man’s satisfaction is greater than another’s is not capable of scientific verification.” I can measure the ranking you have of choices A, B, etc. and compare them with my own ranking. But I cannot measure how much you like A, say, vs. how much I do. Even if event A is top choice for both of us, we cannot say, for example, that I value A the same as you or more than twice as much as you. For the most part modern economists agree that utilities can be compared intra- but not inter-subjectively, as do all behaviorists. I can’t know how you really feel, and vice versa: “Is she really sad or is it just an act?” Nevertheless, in practice interpersonal utility comparisons are commonplace not only in welfare economics but in moral philosophy.
Second, Robbins points out that:
If we disagree about ends it is a case of thy blood or mine—or live or let live according to the importance of the difference, or the relative strength of our opponents. But if we disagree about means, then scientific analysis can often help us resolve our differences. If we disagree about the morality of the taking of interest (and we understand what we are talking about), then there is no room for argument.
Robbins here highlights a large difference between statements of fact, scientific claims, and statements of value. In the case of a scientific claim, there are three possible outcomes: true, false, or “don’t know.” And, importantly, in any given case most rational people will agree on one of these: X is true or not, or we don’t know. But moral claims rarely lead to unanimity. It’s “thy blood or mine—or live or let live according to the importance of the difference.”
Robbins later moderated some of the views expressed in the 1932 book, but emphatically not this one: “I have the strong suspicion that imperviousness to the distinction between ‘is’ and ‘ought’ and its methodological implications is an inborn disability not to be eradicated by argument.”5
Of course, a moral claim can always be converted to a scientific/factual one, as Hume himself suggested. Not “adultery is wrong,” but “Christian doctrine says that adultery is wrong.” But somehow, Putnam et al. still seem to think there are “moral facts” with much the same epistemic status as the facts of science.
Putnam seems to be more concerned with the demotion of value than any change in the nature of fact. For him, some values have the status of facts:
THE IDEA THAT “VALUE JUDGMENTS ARE SUBIECTIVE” is a piece of philosophy that has gradually come to be accepted by many people as if it were common sense. In the hands of sophisticated thinkers this idea can be and has been developed in different ways. The ones I shall be concerned with hold that “statements of fact” are capable of being “objectively true” and capable, as well, of being “objectively warranted,” while value judgments, according to these thinkers, are incapable of object truth and objective warrant…. This book tries to show that from the beginning these views rested on untenable arguments and on over-inflated dichotomies.
So, what is Putnam’s argument? Partly it consists in coining new terms: the distinction between “basic” and “non-basic” value judgments, for example. “A value judgment can be called ‘basic’ to a person if no conceivable revision of factual assumptions can make him revise the judgment.”6 Are “basic” judgments then just Kant’s analytic judgments? Well, maybe, but not just: factual (synthetic) judgments are included. So what does “basic” add? Is a “basic” judgment then just a (moral) fact? The best that can be said of “basic” is that it means that there are some moral statements that will garner the same kind of general assent as well-established scientific factual claims. What is left out, of course, is where this fictional assenting person comes from, his community. One community may be unanimous on the punishment for Koran-burning; another may be indifferent.
This is problematic, because many moral claims will be generally assented to in the right community: Christians will all agree that polygamy is wrong, Muslims will agree that it’s just fine. Perhaps there are moral imperatives to which every cultural community will concur, a general version of the good. But that is precisely what Cambridge philosopher G. E. Moore disproved. To claim that moral claims can be proved by looking at simple facts was called by Moore, the naturalistic fallacy. Yet that seems to be precisely what Putnam et al. are claiming. We can’t be sure, because Moore is mentioned just once in The Collapse of the Fact/Value Dichotomy.
But there are at least two things on which we can agree: First, that finding universal moral claims will be difficult. Second, every one of them impels us to action. If something is bad, we must prevent it; if it is good, we must help it.
Neither of these things is true of scientific claims; there are plenty to be found and unless a value is added, they do not impel us to action.
So really the issue is pretty simple. First, the distinction is not so much between values and facts, but between “is” and “ought,” between a fact or a factual claim (science is always subject to revision, hence “factual claim” rather than “fact”) and a claim that implies the need for action (“ought”). So, the irrefutable distinction is between a factual, scientific claim, i.e., a claim that is susceptible to refutation and requires no other action; and a statement that does imply a need for action because of its moral valence, in other words, between “is” and “ought.”
How well does this version of the distinction survive Putnam’s counterexamples? Is a statement such as “X is cruel” factual or value-laden? Hume had an answer: it depends on context. What is X’s environment? Who is he cruel to? Has that person done anything to injure X? And so on. In other words, define what you mean by “cruel” then ask whether the facts of the case satisfy that definition. Thus, moral statements of this sort can usually be restated either in value form—“He is cruel and that is bad”—or “His behavior can be labeled ‘cruel’ for the following reasons.”
In science, especially social science, there is no basis for denying the is-ought distinction and grave costs for rejecting it. Take for example racist science, a smear often directed at students of cognitive differences between racial groups. ChatGPT conveniently lists examples of “racist science”: Most commonly, the phrase refers to nineteenth and twentieth century efforts to use science to legitimize racism. Examples include: craniometry (measuring skulls), phrenology, racial typologies, eugenics, and claims that some “races” were biologically superior or inferior.
These are either not racist (any objective measurement) or not scientific (any value judgment). So, craniometry is just measuring skull configuration; phrenology is a factual claim about the relation between skull formation and mental faculties. It turned out to be false, but still a factual claim not a moral one. Or take the notion that racial typologies, stereotypes, for the most part have some basis in fact.7 Again, factual claims, partially correct.
Finally, an example of something that is actually racist. Eugenics is based on science: individual differences, cognitive and other, are partially heritable. But the urge to do something about it is moral and political, not part of science. And so are any non-quantitative, value-based claims about the inferiority or superiority of one group compared to another.
Blurring the is-ought distinction has had disastrous effects on research on individual and group differences, especially cognitive differences. Familiar examples are the vicious attacks on researchers such as Arthur Jensen, Charles Murray, and Richard Lynn. The late Philippe Rushton has had many of his papers, all describing quantitative differences, either rejected or retracted. This work was canceled not because it is scientifically flawed (although some of it may be), but because it drew attention to behavioral differences correlated with racial characteristics, which are partially heritable.
Here are two examples. First, an opinion piece by political scientist Lawrence M. Mead which suggested that many of the failures of anti-poverty programs are due to cultural differences:
Some scholars now attribute poverty to culture in the sense that many poor become disillusioned and no longer seek to advance themselves. More plausible is cultural difference. The United States has an individualist culture, derived from Europe, where most people seek to achieve personal goals. Racial minorities, however, all come from non-Western cultures where most people seek to adjust to outside conditions rather than seeking change. Another difference is that Westerners are moralistic about social order, demanding that behavior respect universal principles, while in the non-West norms are less rigid and depend mostly on the expectations of others. These differences best explain why minorities—especially blacks and Hispanics—typically respond only weakly to chances to get ahead through education and work.8
Mead’s paper was retracted by the Springer-Nature journal Society after hundreds of complaints from other social scientists. Mead could not, of course, prove his suggestion. But he was making a reasonably argued factual claim which should have been publishable. He proposed a hypothesis which the retraction ensured will never be studied scientifically. Instead, all emphasis will be on the favored causes of poverty while the cultural possibility is ignored.
A rather striking more recent example is a 2024 paper by German psychologist Heiner Rindermann: “Surprisingly low results from studies on cognitive ability in developing countries: are the results credible?” The article was retracted by the Springer Nature journal Discover: Education on September 16, 2024, again after complaints. The abstract reads:
Developing countries achieve surprisingly weak results in international cognitive competence studies. The results are about one to two standard deviations below the average norm-values obtained in Western countries. The results are so low that they are sometimes difficult to believe. For example, in the World Bank collection, Nigeria scored 262 student assessment points (SASQ, about two and a half standard deviations below the norm 500, equivalent in the IQ-scale to 64 points)…. These results have triggered opposition, factual-scientific criticism, but also ethical debates and political-ideological objections. We crosscheck the values here by comparing different sources of information, statistical analysis, and on-site reports. Results of the different test paradigms seem to be similar for country groups. However, there are sometimes major differences for individual countries. The same is true for comparing different test collections: results of grouped countries are similar, but single countries differ. Using education, GDP per capita and politics to predict test scores shows somewhat higher results for the Global South (5 IQ points), especially for Latin America (rising from 78 to 86 points in an IQ metric). Finally, observational studies of schools and everyday life in several countries of the Global South point to problems in the scope and quality of instruction as well as of thinking.
The articles provide quantitative IQ-related data from a variety of ‘developing countries’ in the Global South, together with interesting personal accounts from the author’s travels in those areas. Some of Rinderman’s observations are fascinating and certainly deserve to be followed up. For example, he comments about his experience traveling by boat for many miles up the winding Rio Cauaburi river in Brazil, and asks every now and then the direction of the West. The landscape is all trees, revealing nothing. Yet the Indian boatman always pointed in the right direction.
There are a number of anecdotes like this, some revealing surprising intelligence of natives, some the opposite. They raise interesting questions even if they do not answer them. Yet they were one reason given by the publisher for rejecting the paper: “the prominence of individual examples taken from the author’s life” even though they are surely worth more than speculation, no matter how buttressed with statistics.
The primary reason for retraction was this: “Independent post-publication peer review has confirmed fundamental flaws in the use of student assessment studies as a measure of IQ or cognitive ability.” This is absurd on its face. How else to assess cognitive ability than by the results of “student assessment studies,” a great variety of which are discussed in the paper?
The real reason for rejection is that Rindermann provided strong evidence for large IQ differences between European and Third World people. At the same time, he quotes Richard Nisbett:
Let’s stop and think for a moment about what an IQ of 70 might mean, if we took it seriously as an actual indicator of intelligence of sub-Saharan blacks…. Given what we know about people with such low IQs in our society, the average African, then, might not be expected to know when to plant seeds, what the function of a chief might be, or how to calculate degrees of kinship. Obviously, something is desperately wrong with these African IQ scores. They cannot possibly mean for the African population what they do for people of European culture.9
And later, Arthur Jensen is quoted:
In social and outdoor play activities… black children with IQ below seventy seldom appeared as other than quite normal youngsters—energetic, sociable, active, motorically well-coordinated, and generally indistinguishable from their age-mates in regular classes. But this was not so for as many of the white children with IQ below seventy. More of them were somehow “different” from their white age-mates in the regular classes. They appeared less competent in social interactions with their classmates and were motorically clumsy or awkward.10
The very different way in which low IQ presents itself in different groups points to huge gaps in our understanding of cognitive ability, gaps which have been ignored because of the inability of many social scientists to separate facts from the emotional valence attached to them.
Let us remember Hume, and cast Hilary Putnam into the scholarly waste-basket together with his arrogant dismissal of a vital distinction.
John Staddon is James B. Duke Professor of Psychology and Professor of Biology emeritus at Duke University; jers@duke.edu. Three of his most recent books are The New Behaviorism: Foundations of Behavioral Science, 3rd edition (Psychology Press, 2021), Unlucky Strike: Private Health and the Science Law and Politics of Smoking, 2nd edition, (PsyCrit Press, 2022), and Inevitable Differences: An Inquiry into Human Variation (Academica, 2026). He last appeared in these pages in spring of 2024 “Truth as a Consensus of Experts,” a review of The Constitution of Knowledge: A Defense of Truth.
1 David Hume, An Enquiry Concerning Human Understanding, (1777/1993 Hackett, London).
2 For a discussion of causation in economics, see, for example, John Staddon, Experimental Method: How Science Works, Fails to Work, and Pretends to Work (Routledge, 2022).
3 F.A. Hayek, The Fatal Conceit: The Errors of Socialism (University of Chicago Press, 1988), 76.
4 Lionel Robbins, On the Nature and Significance of Economic Science (London: Macmillan, 1932).
5 Lionel Robbins, Autobiography of an Economist (Macmillan, 1971).
6 Amartya Sen, “The Nature and Classes of Prescriptive judgments,” Philosophical Quarterly, 17, no. 66 (1967): 46-62.
7 Lee Jussim, Jarret T. Crawford, Kentaro Fujiwara, Rachel S. Rubinstein, “Stereotype Accuracy: One of the Largest and Most Replicable Effects in All of Social Psychology,” in The Oxford Handbook of Social Cognition, ed. Donal E. Carlston (New York: Oxford University Press, 2019).
8 Lawrence M. Mead, “Poverty and Culture,” Society (2020), https://doi.org/10.1007/s12115-020-00496-1 (retracted).
9 Richard E. Nisbett, Intelligence and How to Get It: Why Schools and Cultures Count (New York: W. W. Norton & Company, 2009).
10 Arthur R. Jensen, The g Factor: The Science of Mental Ability (Westport, CT: Praeger, 1998).
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