John Tooby and Leda Cosmides 
Center for Evolutionary Psychology, UCSB 
July 7, 1997

Letter to the Editor of The New York Review of Books on Stephen Jay Gould's "Darwinian Fundamentalism" (June 12, 1997) and "Evolution: The Pleasures of Pluralism" (June 26, 1997)

John Maynard Smith, one of the world's leading evolutionary biologists, recently summarized in the NYRB the sharply conflicting assessments of Stephen Jay Gould: "Because of the excellence of his essays, he has come to be seen by non-biologists as the preeminent evolutionary theorist. In contrast, the evolutionary biologists with whom I have discussed his work tend to see him as a man whose ideas are so confused as to be hardly worth bothering with, but as one who should not be publicly criticized because he is at least on our side against the creationists." (NYRB, Nov. 30th 1995, p. 46). No one can take any pleasure in the evident pain Gould is experiencing now that his actual standing within the community of professional evolutionary biologists is finally becoming more widely known. If what was a stake was solely one man's self-regard, common decency would preclude comment.

But as Maynard Smith points out, more is at stake. Gould "is giving non-biologists a largely false picture of the state of evolutionary theory" -- or as Ernst Mayr says of Gould and his small group of allies -- they "quite conspicuously misrepresent the views of [biology's] leading spokesmen."[1] Indeed, although Gould characterizes his critics as "anonymous" and "a tiny coterie," nearly every major evolutionary biologist of our era has weighed in in a vain attempt to correct the tangle of confusions that the higher profile Gould has inundated the intellectual world with.[2] The point is not that Gould is the object of some criticism -- so properly are we all -- it is that his reputation as a credible and balanced authority about evolutionary biology is non-existent among those who are in a professional position to know.

Why is this important? Evolutionary biology is relevant to a large number of fields -- medicine, neuroscience, psychology, psychiatry, cognitive science, molecular biology, etc. -- that sometimes have an impact on human welfare. Many scientists in these fields look to Gould, as America's most famous evolutionist, for reliable guidance on his field, and so the cumulative effect of Gould's "steady misrepresentation" has been to prevent the great majority of leading scientists in these disciplines from learning about or profiting from the rapid series of advances made in evolutionary biology over the last thirty years. Since these advances have something substantial to contribute to the biomedical, behavioral, and social sciences, the myths and inversions actively cultivated by Gould over the last two decades have materially retarded progress in these fields, a outcome that -- given the human consequences -- one can hardly celebrate.

Now science does not progress by authority or majority, and so biologists do not see his heterodox macroevolutionary speculations, for example, as a problem (they make him interesting, and have occasionally provoked some genuinely worthwhile discussion)[3]. For biologists, the central problem is that Gould's own exposition of evolutionary biology is so radically and extravagantly at variance with both the actual consensus state of the field and the plain meaning of the primary literature that there is no easy way to communicate the magnitude of the discrepancy in a way that could be believed by those who have not experienced the evidence for themselves. Gould has pioneered something new in letters, something practitioners of science studies would find well worth studying: anti-Gricean science.

Grice argued that interpreting the meaning of utterances is only possible because listeners implicitly assume that speakers intend their utterances to be responsive to the surrounding discourse, relevant, and (for the most part) truthful. Gould's writings are full of brilliant rhetorical devices that violate and so exploit these Gricean assumptions. For example, one of Gould's many anti-Gricean devices is to pound the table about the truth of obviousities (e.g., "But does all the rest of evolution...flow by simple extrapolation from selection's power to create good design of organisms?" or -- our personal favorite -- "I do not believe that members of my gender are willing to rear babies only because clever females beguile us") implicitly persuading any sane listener that his opponents or some important consensus somewhere must hold the opposite and absurd view, if only in some toned down form. In this series, Gould deploys this but-I-tell-you-the-sun-really-does-rise-in-the-east device hebephrenically.

As a immensely popular writer, Gould is conscious that he is paradoxically safe from exposure in whatever he asserts because only minuscule number of his readers will actually consult the original sources, with all the rest trusting his warmly benevolent and credible persona. He uses this insulation to devastating effect. Everyone who overhears only one side of a conversation (such as the 99% of his readership who are exposed only to Gould's accounts) automatically reconstructs what the other side of the conversation must have been, in order to make Gricean sense of why, for example, Gould said what he did. Literature and life are full of cases where the unscrupulous exploit situations in which they know the audience can only hear their side of the conversation to paint a wholly false picture of the opinions and actions of the other speaker. The senator who screams "Take away your filthy bribe!" utterly persuades onlookers of what the other person must have said in a way that makes further inquiry scarcely seem worth the effort. Fortunately for the interested few, in the sciences we have a "security camera" called the primary literature that can actually provide the other side of the conversation. When the background literature is filled in, the picture of Gould inverts like a Necker cube, and his essays become revealed as mini-theatricals carefully staged for purposes of self-aggrandizement rather than for the careful and charitable pursuit of the truth. We propose to roll back the "security camera" by consulting the primary literature that Gould pretends to be reacting against in his recent outburst, and compare against his critical claims.

What are these claims? Gould affirms that he, like Darwin, is an eminently sensible pluralist who sees that "natural selection has been the main but not the exclusive means of modification." He contrasts his (lip-service) pluralism with its "uncompromising" and "fanatical" opposite -- the "strict" "dogmatic" (and wholly imaginary) doctrine of attributing "everything of any importance in evolution" to selection, which for his targets supposedly becomes the "effectively exclusive" explanation for "all the phenomena of organic diversity" from mass extinctions to silent nucleotide substitutions. He then (incredibly) sets about lecturing evolutionary biologists about a series of self-evident commonplaces of our field, implying (e.g., "My third pluralistic corrective to traditional theory"...) or stating in his best but-the-sun-does-rise form that these are either almost unknown to or play little or no role in the scientific practice of "traditional" evolutionary biologists and evolutionary psychologists. He claims to "take up the methodology" of evolutionary psychology and baldly states that "disciples of this new art confine evolutionary accounts to the workings of natural selection and consequent adaptation for personal reproductive success." In particular, any reader of English would understand Gould to be specifically claiming that we are panglossian panadaptationists (although perhaps retrospective panglossians), are either unaware of or do not use neutral theories of evolution in our work, never consider or test byproduct hypotheses, are unaware that byproducts and constraints exist and are ubiquitous in the design of organisms, are befuddled by the pervasiveness of contingency in evolution, spend our time concocting "untestable" and hence "unscientific" post hoc just so stories, and so on.

In order to measure these claims against the primary literature, however, it is important to recognize that we are clearly prime exemplars of who and what Gould felt he was attacking in his two part series. Gould would have to stipulate this not just because we (with Symons, Daly & Wilson, Buss, Shepard, Pinker, and a few others [4]) are the researchers most often associated with the emergence of evolutionary psychology, but because (1) he cites our book The Adapted Mind explicitly in his attack as one of two key texts (and in fact the only nonpopular treatment cited), and (2) our reasoning work is the only actual research in evolutionary psychology that Gould manages to specifically discuss in his entire two article peroration. Moreover, as scientists who have been trained and published in evolutionary biology in addition to psychology and anthropology, we are entirely representative of the evolutionary biologists Gould targets as well. If there is any truth whatsoever in what Gould says about evolutionary psychologists, adaptationists, or evolutionary biologists, it would have to be true of us, and so our work can fairly serve as a test case for Gould's essential accuracy.

With this in mind, the issue we will be addressing is, are Gould's characterizations of his opponents' positions intelligible exaggerations (e.g., saying we use adaptationist principles exclusively when he means "more than I care for"), do they move beyond exaggeration into the incoherently wrong (e.g., confusing cabbages with concubinage), or indeed do they often transcend being completely wrong by aspiring to achieve the reverse of the truth (e.g., locating the orbit of the moon within the Earth's core).

We will start with Gould's first concrete statement about us. In it, he characterizes the proposed function of the cognitive specializations that we have experimentally investigated [5] as "the ability to detect infidelity and other forms of prevarication." This is scores as completely wrong: the proposed mechanism does not detect infidelity or deception, nor has anything whatsoever to do with either deception or infidelity. Instead it is an enhanced cognitive ability to reason about instances of compliance and noncompliance in situations of reciprocal cooperation. This level of scholarly inaccuracy is entirely standard for Gould whether discussing biology or psychology, but we admit it registers only as a gross error (e.g., confusing Hoagy Carmichael with Stokely Carmichael) and not as a complete mirror reversal of the truth.

So what does the primary literature say about his bill of particulars on ultra-Darwinism? The few who bother to look at the chapter that Gould discusses on our reasoning experiments should be astonished to discover that we tested not only an adaptationist hypothesis about human reasoning, but six different byproduct hypotheses as well (byproduct hypotheses are derived and tested regularly in our empirical papers, as they are routinely in other "adaptationist" research in evolutionary psychology and biology). Indeed, one literally could not open any paper of ours on psychology (including the ones Gould cites) without finding careful discussions of adaptations, byproducts, and features present through neutral drift or chance, along with other determinants of evolutionary outcomes ("mutation, recombination, genetic hitch-hiking, antagonistic pleiotropy, engineering constraints, antagonistic coevolution" etc., etc.). However, rather than being satisfied with Gould's preferred, and anti-empirical, stance that given the plurality of possible explanations there is no way to tell which are true, our papers show an intense concern with the full range of available empirical and conceptual methods for falsifiably distinguishing the effects of chance, byproduct, and selection.

But what about our "sterile" and "impoverished" neglect of the "rich" theory of neutralism? In our 1982 work proposing that parasite pressure drove the evolution of sex and the maintenance of genetic polymorphism, we explicitly used neutralist theories of evolution to evaluate contrasting predictions about the distribution of alleles driven by chance vs. frequency-dependent parasite pressure. In this way we were and are no different than any other adaptationist biologist, who use molecular clocks and other applications of neutralism routinely in research, as well as, for example, random walk and byproduct null hypotheses. Several years later, we integrated these theories about polymorphism and parasitism with other selectionist and nonselectionist findings to derive a possible reconciliation for the apparently contradictory empirical discoveries of (1) a Gray's Anatomy-style species-typical human design and (2) the discovery by Lewontin and others of large reservoirs of genetic differences between humans. In that article, we derive the result that "most heritable psychological differences are not themselves likely to be complex psychological adaptations. Instead they are mostly evolutionary byproducts, such as concomitants of parasite-driven selection for biochemical individuality..." or "genetic noise" -- and go on to say that researchers will find it useful to identify the "differences that are adaptive (the smallest category), (b) differences that are maladaptive, and (c) differences that are effectively neutral (the largest category)." Here we claim that thousands of interesting psychological phenomena (of interest to psychopharmacologists, psychiatrists, behavior geneticists, personality psychologists, etc.) are not adaptations, but are byproducts of adaptations, negative mutations, or are the results of the neutral genetic variants analyzed in Kimura's theory.

Regarding historical contingency, in our 1981 paper attempting to derive the principles of intragenomic conflict, we wrote that "the particular sequence of intragenomic events may explain major trait sets in a way that the simple appeal to ecological circumstances by themselves cannot. This gives an unstable, interactive, and historical character to the evolutionary process." As for panglossian attributions of optimality, we go on to say that this conflict and its byproducts may explain why genetic systems "are so filled with non-optimal aberrations."

We mention this paper (aside from crossing two other false accusations off the list) because of the light it throws on both Gould's attitudes towards empiricism, and his campaign to stigmatize Dawkins, the brilliant and authentic native voice of modern evolutionary biology. For twenty years Gould has showered Dawkins with abuse, ostensibly because Dawkins has argued (in Gould's present lame rendering) that "genes struggl[e] for reproductive success within passive bodies (organisms) under the control of genes -- a hyper-Darwinian idea that I regard as a logically flawed and basically foolish caricature of Darwin's genuinely radical intent." Foolish it may sound, and wrong it might have been, but in all these years it has seemingly not occurred to Gould to look at the natural world to see. This is just what Eberhardt and we did in parallel papers on intragenomic conflict -- we derived clear predictions from the Dawkins/Williams view of the reality of genic selection as distinct from individual selection, and substantiated them with scores of well-documented phenomena. Now Gould may understandably have missed those early papers, but 17 years of subsequent papers by Hurst, Hamilton, Haig, Skinner, Werren and dozens of others in Science, Nature, Evolution, etc., have provided a formidable body of empirical support for these and newer predictions about intragenomic conflict. This flood of publications would have led an honest and scholarly soul to admit that Dawkins has been brilliantly vindicated, or led a more abashed soul to at least become silent on the subject, but it has led our anti-Gricean simply to repeat the charges unamended even unto his latest article, falsely communicating to his audience the natural world has had nothing to say on the subject. Equally, no competent modern evolutionary biologist would use the phrase or concept of "personal reproductive success" as Gould does for "the Darwinian summum bonum" that defines what selection favors. This is not just because the phenomena of intragenomic conflict deconstruct that concept from below, but more profoundly because, at least since Hamilton's classic work in 1964, biologists have recognized that selection will favor decrements in individual reproductive success if that sufficiently enhances the reproduction of kin. (Indeed, Gould's writings in general so often lack any evident awareness of modern theories, distinctions, and tools, that they give the impression to the biologically educated of someone who has been "cutting class" for the last thirty years.)

The "just so" story inversion: Gould once again propagates his famous claim, accepted naively by nonbiologists, that the adaptationist program as practiced by leading researchers consists inherently of post hoc and unfalsifiable storytelling about the imagined ancestral functions of design features that one already knows about. This exactly reverses the practice: Given that we know so little about the human brain and cognitive architecture, what researchers most desperately need are powerful theoretical tools that can help them design experiments to more efficiently search for otherwise unsuspected organization -- that is, for design features that have not yet been observed. Modern selectionist theories are used to generate rich and specific prior predictions about new design features and mechanisms that no one would have thought to look in the absence of these theories, which is why they appeal so strongly to the empirically minded. It may certainly turn out, for example, that we are wrong in our heterodox view that the faculty of human reasoning includes a large and heterogeneous set of evolved, functionally specialized circuits (for cooperation, threat, hazard avoidance, etc.). But the point is that modern evolutionary functionalism led to a series of predictions about human reasoning that no one would otherwise have thought to make or to test, and so to discoveries that would otherwise not have been made (including of neural dissociations along predicted functional dimensions of exactly the kind Gould claims evolutionary psychologists have not provided). As we pointed out in the Adapted Mind, "an explanation for a fact by a theory cannot be post hoc if the fact was unknown until after it was predicted by the theory and if the reason the fact is known at all is because of the theory...". Even when adaptationists start with a known phenomenon, hypotheses about function are used to make predictions about new and uninvestigated aspects of design. Indeed, an exasperated George Williams and Randy Nesse, in their classic appeal to the medical community to learn about and exploit modern evolutionary principles in their research [6], were driven to construct a table of new adaptationist discoveries reported in just a single volume of the journal Evolution, in a vain attempt to counter this widely credited urban legend.

It is exactly this issue of predictive utility, and not "dogma", that leads adaptationists to use selectionist theories more often than they do Gould's favorites, such as drift and historical contingency. We are embarrassed to be forced, Gould-style, to state such a palpably obvious thing, but random walks and historical contingency do not, for the most part, make tight or useful prior predictions about the unknown design features of any single species.

This brings us finally to Gould's misrepresentation, delivered in his best anti-Gricean form, on the impossibility of knowing the past. "But how could we possibly obtain the key information that would be required to show the validity of adaptive tales about an EEA [i.e., the environment in which humans evolved]?" Well, as the Adapted Mind makes clear, the goal of evolutionary psychology is to learn about the design of modern humans, rather than, as Gould claims, to "show the validity of adaptive tales" about the past. Yet Gould's argument that we can know nothing reliably enough about the ancestral world from which to derive useful predictions is marvelously telling about Gould, given that he has ostensibly dedicated his life to the scientific study of the past. It is, nonetheless, patently false.

Those who actually work across disciplines on the inferential reconstruction of the past realize that we know with certainty thousands of important things about our ancestors -- many of which can be useful in guiding psychological (or e.g., medical) research: Our ancestors nursed, had two sexes, hunted, gathered, chose mates, used tools, had color vision, bled when wounded, were predated upon, were subject to viral infections, were incapacitated from injuries, had deleterious recessives and so were subject to inbreeding depression if they mated with siblings, fought with each other, lived in a biotic environment with felids, snakes, and plant toxins, etc. It is a certainty that our ancestors lived in a world in which the principles of kinematic geometry governed the motions of objects (a set of facts that allowed Roger Shepard to develop his theories about the evolutionary foundations of psychophysics that, in part, won him the National Medal of Science). It is equally a certainty that hominids had eyes, looked at what interested them, and absorbed information about what they were looking at, making eye-gaze direction informative to on-lookers. Simon Baron-Cohen, at Cambridge University, has elaborated a subtle and far-reaching research program based on these obvious facts about the ancestral world, leading to the discovery of a series of important cognitive, developmental, and neural phenomena. And obviously, one can derive valuable experimental hypotheses even from possible rather than certain features of the ancestral world, while the many features of the ancestral world about which we are ignorant simply do not form the basis for experiments.

So, on our lack of pluralism, on neutralism, on confining ourselves to selectionist stories, on a failure to consider or test byproduct hypotheses, on genic selectionism, on post hoc accounts, etc., Gould has demonstrably gone far beyond simple exaggeration, far beyond the wildly erroneous and has sprinted back to his favorite haunt -- the land of joyous, abandoned, systematic, and hilarious inversions of the truth. He cannot plead either ignorance, or that we are unrepresentative, since he picked us as his paradigm examples, he picked and enumerated his grounds for criticizing us, and he even picked the texts on which these issues could fairly be judged (all the points mentioned above are clearly reviewed in the sources he cited, with the exception of intragenomic conflict, which is only minimally mentioned in The Adapted Mind, although well-known to anyone who has read a textbook or journal in the last decade). And excepting macroevolution, these are even the themes on which he built his career, and so on which he can be expected to have special expertise. If he is so wrong here, on what ground less familiar to him can he be trusted as an authority, or even a confused reporter, struggling to get the gist?

What is so sorry about this situation is not that this is a rare excess of Gould's, but rather that it is not. Biologists will recognize this as completely representative of his usual spectacular distortions of evolutionary biology. What is unrepresentative about this case is that Gould exposed himself to the possibility of being tested by a moment of incautious specificity in which he cited one primary text, and did so in a widely read forum that takes letters.

This brings us to, in the eyes of evolutionary biologists, the single most significant and amazing of Gould's mirror reversals -- the panadaptationism inversion: Gould has nearly made a career of claiming that modern evolutionary biologists suffer from a tendency to uncritically overattribute adaptation. The accusation of panglossianism is widely and uncritically believed on Gould's authority by those too distant from the primary literature to know better. What Gould knows, and trusts the reader not to know, is that the revolution in evolutionary biology that began in the 1960's was rooted exactly and specifically in a widespread reaction against and rejection of the practice of overattributing adaptation. That is, what defined the emergence of modern adaptationism as both a community and set of theories was just this anti-panglossian revolution. In Adaptation and Natural Selection -- what has been described both as the most important book in evolutionary biology written in this century, and the defining volume in modern adaptationism -- George Williams begins his summary in the table of contents by saying "Evolutionary adaptation is a special and onerous concept that should not be used unnecessarily, and an effect should not be called a function unless it is clearly produced by design and not by chance. When recognized, adaptation should be attributed to no higher a level of organization than is demanded by the evidence." These are the very first words in the book. It was just this adaptationist community who cleansed biology of panglossianism, panadaptationism, fuzzy attributions of function, teleology, and progress by a series of theoretical advances (inclusive fitness theory, refinements on the units of selection, falsifiable criteria for judging adaptation and its absence, etc.). In the years that followed, they won this debate by establishing clear standards of evidence, a tradition of rigorous hypothesis testing, and by being very restrictive and narrowly selective in the scope of phenomena entertained as potential candidates for functional explanation (indeed, as we shall see, more restrictive than Gould is). Gould, starting over a decade later, borrowed this critique without attribution. Amazingly, Williams' book and other similar references are simply not cited by Gould in his critiques in what must qualify as one of his most brazen examples of anti-Gricean manipulation, because he then turns around and diametrically misrepresents the very community from which he drew his ideas.

Ironically, one of the theories that this revolution cast into doubt as a probable panglossian overextension was the idea that species selection plays a prominent role in building adaptations. Gould conceals this, for this is a panglossian overextension that Gould himself champions, as one dimension of his views on punctuated equilibrium. So Gould's claim in this series that "The study of mass extinction has also disturbed the ultra-Darwinian consensus" is yet still another inversion (who can keep up?), for random contingency in species extinction (as opposed to the selection of alternative alleles in populations) would only disturb species selectionists. And, as Dawkins mordantly asks in his review of Wonderful Life, "who is the most prominent advocate of higher-level selection today?"

Now, given the foregoing, one is left with the puzzle of why Gould so customarily reverses the truth in his writing. We suggest that the best way to grasp the nature of Gould's writings is to recognize them as one of the most formidable bodies of fiction to be produced in recent American letters. Gould brilliantly works a number of literary devices to construct a fictional "Gould" as the protagonist of his essays and to construct a world of "evolutionary biology" every bit as imaginary and plausible as Faulkner's Yoknapatawpha County. Most of the elements of Gould's writing make no sense if they are interpreted as an honest attempt to communicate about science (e.g., why would he characterize so many researchers as saying the opposite of what they actually do) but come sharply into focus when understood as necessary components of a world constructed for the fictional "Gould" to have heroic fantasy adventures in -- adventures during which the admirable character of "Gould" can be slowly revealed.

In the course of these engaging tales, Gould the author introduces us to a gallery of vivid villains and ethnicities, such as "adaptationists," "Dawkins" and the soulless "hyperreductionists" with their vivisectionist appetites, "Wilson" and the sinister "sociobiologists", "biological determinists," and most recently, the holy-rolling "Darwinian fundamentalists," including "Maynard Smith" with his "simplistic dogmatism," "Dennett," "evolutionary psychologists," and "Robert Wright." "Gould" the protagonist is a much loved character (and not just in our household) who reveals himself to be learned, subtle, open-minded, tolerant, funny, gracious to his opponents, a tireless adversary of cultural prejudice, able to swim upstream against popular opinion with unflinching moral courage, able to pierce the surface appearances that capture others, and indeed to be not only the most brilliant innovator in biology since Darwin, but more importantly to be the voice of humane reason against the forces of ignorance, passion, incuriousity, and injustice. The author Gould, not least because he labors to beguile his audience into confusing his fictional targets with actual people and fields, is sadly none of these things.

Since Gould is not, in fact, more insightful than other evolutionary biologists, the real world of evolutionary biology cannot offer the ready victories and surmountable challenges that Gould needs to establish the heroism of "Gould." So real evolutionary biology must be abolished. If as a byproduct or spandrel of this abolition, a generation of scientists and general readers alike are miseducated, that is a small price to pay. And indeed the whole post-1964 edifice of modern evolutionary biology built by Williams, Hamilton, and Maynard Smith and scores of others is left out of Gould's books, which is something like leaving quantum mechanics out of the history of 20th century physics.

Yet in the final analysis, there are genuine grounds for hope in the immense and enduring popularity of Gould. Gould is popular, we think, because readers see in "Gould" the embodiment of humane reason, the best aspirations of the scientific impulse. It is this "Gould" that we will continue to honor, and, who, indeed, would fight to bring the illumination that modern evolutionary science can offer into wider use.

John Tooby & Leda Cosmides, Co-Directors,
The Center for Evolutionary Psychology
Depts. of Anthropology & Psychology
University of California, Santa Barbara

Full text of Gould's article | Back to CogWeb's Debate page


(1) Mayr, Ernst 1988 Toward a new philosophy of biology. Harvard University Press, pp. 534 - 535. Back

(2) These include Ernst Mayr, John Maynard Smith, George Williams, Bill Hamilton, Richard Dawkins, E.O. Wilson, Tim Clutton-Brock, Paul Harvey, Brian Charlesworth, Jerry Coyne, Robert Trivers, John Alcock, Randy Thornhill, and many others. Back

(3) But for Gould's inability to be either self-consistent or empirically oriented even about his own macroevolutionary views, see the recent exchange with Coyne & Charlesworth in Science. Back

(4) For a guide to the primary literature in evolutionary psychology, see Back

(5) An overview of evolutionary psychology is given in "The psychological foundations of culture" in The Adapted Mind, and the reasoning experiments are reported in the chapter "Cognitive adaptations for social exchange." The other papers discussed are cited in the references to the Adapted Mind. Back

(6) George C. Williams and Randolph Nesse, 1991, "The dawn of Darwinian Medicine" in The Quarterly Review of Biology 66: 1-22  Back