Steven Pinker’s thoughtful remarks concerning group selection present a useful occasion for clearing some misconceptions surrounding recent developments in the behavioral sciences concerning our understanding of moral vs. self-interested behavior. Initiated in 1966 by George C. Willams’ Adaptation and Natural Selection and followed a decade later by Richard Dawkins’ The Selfish Gene, evolutionary biologists in the last quarter of the Twentieth century came to view humans as fundamentally selfish, contributing to society only when socially-imposed rewards and punishment render it in their self-interest to do so. Dawkins, for instance, opines in the opening pages of The Selfish Gene, “We are survival machines—robot vehicles blindly programmed to preserve the selfish molecules known as genes…. a predominant quality to be expected in a successful gene is ruthless selfishness. This gene selfishness will usually give rise to selfishness in individual behavior…. Anything that has evolved by natural selection should be selfish.”
Of course, it does not appear in our daily life that everyone is selfish, and if we introspect, most of us will agree that we try to behave, however successfully or unsuccessfully, as moral beings willing to sacrifice personal amenities in the pursuit of truth, justice, loyalty and compassion. Dawkins’ explanation is that human morality is a cultural facade laid upon our basically selfish human nature. “Be warned,” he states, “that if you wish, as I do, to build a society in which individuals cooperate generously and unselfishly towards a common good, you can expect little help from biological nature. Let us try to teach generosity and altruism, because we are born selfish.”
But why do fundamentally selfish beings, which is what humans are according to the selfish gene theory, accept cultural norms that contradict their natural strivings? Richard Alexander answered this question in 1987 in his The Biology of Moral Systems with his concept of indirect reciprocity, according to which we all continually evaluate others for possible future gainful interactions, and we reject individuals who violate norms of reciprocity. The somewhat more general answer offered by Pinker is that is that each of us conforms to social norms out of fear of losing our good reputation. What appears to be self-sacrifice is thus simply a superficial veneer covering our selfish natures. “Scratch an altruist,” biologist Michael Ghislin eloquently wrote in 1974, “and watch a hypocrite bleed.”
Pinker frames the issue in terms of sacrificing personal interests on behalf of the group. “What we don’t expect to see,” he writes, “is the evolution of an innate tendency among individuals to predictably sacrifice their expected interests for the interests of the group.” This is not the correct way to frame the issue. People do not generally “sacrifice on behalf of the group.” Rather, people have moral principles that the strive to uphold, and that compete with their material interests. When I behave honestly in a transaction, I may have no intention whatsoever of sacrificing on behalf of my transaction partners, much less on behalf of my society. I just do what I think is the morally correct thing to do. When I bravely participate in a collective action against a despotic regime, I am upholding my moral principles, not sacrificing on behalf of the group. Indeed, it is no sacrifice at all to behave morally, because we humans care about our moral worth in much the same way as we care about our material circumstances.
The past few decades have seen the massive accumulation of evidence in favor of the view that human beings are inherently moral creatures, and that morality is not a simple cultural veneer. Humans are born with a moral sense as well with a predisposition to accept and internalize moral norms their society, and often to act on these moral precepts at personal cost. In our book, A Cooperative Species, Samuel Bowles and I summarize a plausible model of human nature in which “people think that cooperating is the right thing to do and enjoy doing it, and that they dislike unfair treatment and enjoy punishing those who violate norms of fairness.” Most individuals include moral as well as material goals in their personal decision-making, and they willingly sacrifice material interests towards attaining moral goals. It is this view that I will defend in my remarks.
Pinker does not present, and indeed makes light of the body of research supporting the existence of a basic human moral sense, suggesting that there is only one piece of evidence supporting the view that people behave morally when their reputations are not at stake: “It seems hard to believe,” he says, “that a small effect in one condition of a somewhat contrived psychology experiment would be sufficient reason to revise the modern theory of evolution, and indeed there is no reason to believe it. Subsequent experiments have shown that most of the behavior in these and similar games can be explained by an expectation of reciprocity or a concern with reputation.” Because expectation of reciprocity and concern for reputation are basically selfish and do not involve a fundamental respect for moral values, Pinker is simply reiterating Dawkins’ message of a half-century ago that we are the selfish product of selfish genes.
1. Morality and Human Nature
Today the economics and psychology journals, including the most influential natural science journals, Science and Nature, are full of accounts of human moral and prosocial behavior. Pinker dismisses this evidence by asserting that “Any residue of pure altruism” beyond self-interested reciprocity and reputation building “can be explained by the assumption that people’s cooperative intuitions have been shaped in a world in which neither anonymity nor one-shot encounters can be guaranteed.” In other words what looks like moral behavior is just a form of mental error due to imperfections of the human brain.
The empirical evidence on cooperation in humans does not support Pinker’s view. The social interactions studied in the laboratory and field always involve anonymity, so subjects cannot help or harm their reputations, and they usually are one-shot, meaning that subjects cannot expect to be rewarded in the future for sacrifices they make at a given point in time.
Pinker does cite a few studies that support his position. “Subsequent experiments have shown that most of the behavior in these and similar games can be explained by an expectation of reciprocity or a concern with reputation.” Let us see what these studies in fact say. Reciprocity, says Pinker, “is driven not by infallible knowledge but by probabilistic cues. This means that people may extend favors to other people with whom they will never in fact interact with again, as long as the situation is representative of ones in which they may interact with them again.” The only published paper he cites is by Andrew W. Delton, Max M. Krasnow, Leda Cosmides and John Tooby, “Evolution of Direct Reciprocity Under Uncertainty can Explain Human Generosity in One-shot Encounters.” This paper (and several related papers coming out of the Center for Evolutionary Psychology at Santa Barbara, California) show that, in the authors’ words “generosity is the necessary byproduct of selection on decision systems for regulating dyadic reciprocity under conditions of uncertainty. In deciding whether to engage in dyadic reciprocity, these systems must balance (i) the costs of mistaking a one-shot interaction for a repeated interaction (hence, risking a single chance of being exploited) with (ii) the far greater costs of mistaking a repeated interaction for a one-shot interaction (thereby precluding benefits from multiple future cooperative interactions). This asymmetry builds organisms naturally selected to cooperate even when exposed to cues that they are in oneshot interactions.”
This statement is of course not only true, but completely obvious, and does not require sophisticated academic papers to validate its truth. However it does not explains human generosity. It is elementary logic that to say that P explains Q does not mean that if P is true then Q is true, but rather the converse: whenever Q is true, then P is true as well. In the current context, this means that whenever subject A sacrifices on behalf of stranger B in an experiment, it must be true that A is sufficiently uncertain concerning the probability of meeting B again, and A would incur a sufficiently large cost should A meet B again in the future, that it pays A to sacrifice now. The authors have not even attempted to show that this is the case. Nor is it plausible. The experiments under discussion assume subject anonymity, subjects will never knowingly meet again. Pinker’s supposed counter-evidence is thus invalid. To my knowledge, there is simply no credible counter-evidence.
2. Human Morality in Everyday Life
Many readers will doubtless wonder if our view of human moral behavior, which is based on controlled laboratory and field studies, extends to real life. Consider, for one example among many, political activity in modern societies.
In large democratic elections, the selfish individual will not vote because the costs of voting are positive and significant, but the probability that one vote will alter the outcome of the election is vanishingly small. Thus the personal gain from voting is vanishingly small. The cost, however, is a significant amount of time and energy that could have been devoted to other, materially rewarding, purposes. It follows also that a selfish individual will generally not bother to form opinions on political issues, because these opinions cannot affect the outcome of elections.
Yet people do vote, and many do expend time and energy in forming political opinions. This behavior does not conform to the selfish gene model. Of course it could be argued that we only vote to enhance our reputation as a good citizen, but since who votes is normally not public information, and one’s voting history of little interest to employers and other social intimates, this is not a very plausible explanation.
It is a short step from the irrefutable logic of selfish political behavior that selfish individuals will not participate in the sort of collective actions that are responsible for the growth of representative and democratic governance, the respect for civil liberties, the rights of minorities and women in public life, and the like, that are characteristic of many modern societies. In the selfish gene model, only small groups of individuals who seek social dominance will act politically. Yet modern egalitarian political institutions are the result of such collective actions. This behavior cannot be explained by the selfish gene model.
Except for professional politicians and socially influential individuals, electoral politics is a vast morality play to which models of the selfish actor are a very poor fit.
Defenders of the selfish gene theory may respond that voters believe their votes make a difference, however untenable this belief might be under logical scrutiny. Indeed, when asked why they vote, voters’ common response is that they are trying to help get one or another party elected to office. When reminded that one vote cannot make a difference, the common reply is that there are in fact close elections, where the balance is tipped in one direction or another by only a few hundred votes. When reminded that one vote will not affect even such close elections, the common repost is that “Well, if everyone thought like that, we couldn’t run a democracy.” Agreed. But this is just the Kantian categorical imperative, an eminently moral value. People vote because it is simply the right thing to do.
Politically active and informed citizens appear to operate on the principle that voting is both a duty and prerogative of citizenship, an altruistic act that is justified by the categorical imperative: act in conformance with the morally correct behavior for individuals in one’s position, without regard to personal costs and benefits. Such mental reasoning, which has been called “shared intentionality,” is implicated in many uniquely human cognitive characteristics, including cumulative culture and language. Shared intentionality rests on a fundamentally prosocial disposition.
Human beings acting in the public sphere are, then, neither avid reputation mongers nor personal gain maximizers. Rather, they are in general what Aristotle called zoon politikon—political beings. And political beings are moral beings.
3. Cultural Evolution Theory is not Just History
“Most of the groupwide traits that group selectionists try to explain,” says Pinker, “are cultural rather than genetic…. Instead, they are traits that are propagated culturally… group selection … is not a precise implementation of the theory of natural selection… Instead it is a loose metaphor, more like the struggle among kinds of tires or telephones. For this reason the term `group selection’ adds little to what we have always called `history’.” There are two misconceptions in this statement. The first is that group selectionists are for the most part uninterested in genetic evolution. The second is that the concept of cultural evolution is a simply a metaphor.
In fact, the general framework within which we work is called gene-culture coevolution. This framework is quite clearly delineated in scientific terms (see, for instance, my overview, “Gene-culture Coevolution and the Nature of Human Sociality” which I can summarize as follows.
First, as elucidated by Richard Lewontin in 1970, natural selection applies to any entity that follows certain rules. “The principle of natural selection as the motive force for evolution… embodies three principles.” These principles are first, phenotypic variation: “Different individuals in a popUlation have different morphologies, physiologies, and behaviors.” Second, differential fitness: “Different phenotypes have different rates of survival and reproduction in different environments.” And finally, fitness must be heritable: “There is a correlation between parents and offspring in the contribution of each to future generations.” Note that there is nothing about genes in this account of natural selection. Indeed, Darwin himself never heard of genes when he wrote The Origin of Species by Means of Natural Selection. “It is important to note,” writes Lewontin, “a certain generality in the principles. No particular mechanism of inheritance is specified… The population would evolve whether the correlation between parent and offspring arose from Mendelian, cytoplasmic, or cultural inheritance.”
Second, many forms of culture do indeed follow these three principles. Different societies have different cultural norms and technologies (phenotypic variation), some cultural forms contribute more to the fitness of individuals in the societies that embrace these forms, and therefore the cultural forms themselves have varying rates of having copies in succeeding generations (differential fitness), and finally, there is a degree of faithfulness in copying cultural objects from one generation to the next (heritability).
Third, there is a common underlying unity to genetic and cultural evolution. Genes transmit information from one generation to the next, encoded in DNA, that is used by new individuals for ontological development and adaptation to the environment. Cultural forms transmit information from one generation to the next, encoded in human brains, artifacts, and documents, used by new individuals for similar purposes.
Finally, when humans develop new cultural forms, such as language, tools, lethal weapons, control of fire and cooking of edibles, the long-term effect is the transformation of the human genome itself. In other words, cultural evolution leads to genetic evolution. Examples are cooking, which led to a vast reduction in the size of the human gut, language, which led to radical changes in the human larynx and tongue as well as a considerable increase in brain size, and lethal projectile weapons, which led to changes in the morphology of hand and shoulders, as well as a reorganization of the upper torso musculature. Consider, for instance, that our closest relative, the chimpanzee, spends five hours a day digesting comparing to one for humans, lacks the ability to produce complex vocalizations, and cannot throw a stone with more than minimal accuracy or force.
Gene-culture coevolution provides a plausible scenario for the development a moral sense in humans, a quality that appears to be absent or extremely rudimentary in other species. Of course, we may never know with certainty because the paleoanthropological record is extremely scanty. However, it is clear that the development of tools, weapons, and cultural objects required cultural norms promoting cooperation. Individuals who violated these norms were doubtless punished and shunned, and hence less likely to pass their genes on to the next generation. A genetic predisposition to conform to social norms was thus likely to be biologically fit, and hence to evolve through natural selection. Insofar as social norms contribute to the fitness of the groups that embrace these norms, so will the genetic predisposition to follow these norms. We call such a predisposition a moral sense.
4. The Group Selection Pseudo-controversy
Pinker begins his discussion of the group selection issue with the following question. “Human beings live in groups, are affected by the fortunes of their groups, and sometimes make sacrifices that benefit their groups. Does this mean that the human brain has been shaped by natural selection to promote the welfare of the group in competition with other groups, even when it damages the welfare of the person and his or her kin? If so, does the theory of natural selection have to be revamped to designate `groups’ as units of selection, analogous to the role played in the theory by genes?” There are two misconceptions in the very posing of this question.
If an altruistic behavior reduces the net fitness of the altruist and his kin, it cannot evolve. The “group selectionists” argue that while the altruist may be less fit that the selfish individuals in his group, groups with many altruists will expand at the expense of groups with few or no altruists, and this expansion can more than offset the fitness loss of the altruist. Because the altruists kin are more likely to be altruists and also are more likely to be in the altruist’s (this is called `limited dispersal’), the net effect of the altruistic act may be to increase the average fitness of the altruist’s kin.
The first misconception here is the view that group selection is incompatible with kin selection. It is not. Kin selection says that the fitness of an individual depends on the genes of his kin and not just his own genes. Group selection says the fitness of an individual depends on the characteristics of the group he is in, not just his own genes. The second misconception is that group selection means that the group is a “unit of selection.” This is not true. Group selection occurs when the fitness of individuals may be higher in one group rather than other, depending on the social structure of the group and its and distribution of genomes.
A third misconception is that if genes are the only true replicators in evolutionary biology, and if genes are in some sense purely selfish replicators, then all biological species must ultimately sacrifice only for their close genealogical relatives. We can thus admit the complex division of labor and altruism in such eusocial species as termites and honeybees, but we must deny altruism in the case of humans, who cooperate widely with non-relatives. In fact, a careful development of gene-level fitness dynamics in a recent paper by Andy Gardner and J. J. Welsh, “A Formal Theory of the Selfish Genootnote Journal of Evolutionary Biology, 24, 2011. shows that even an inclusive fitness maximizing selfish gene can support altruistic behavior in its owner.
5. The Group Selection Issue is Scientific, not Political
The group selectionists, says Pinker “have drawn normative moral and political conclusions from these scientific beliefs, such as that we should recognize the wisdom behind conservative values, like religiosity, patriotism, and puritanism, and that we should valorize a communitarian loyalty and sacrifice for the good of the group over an every-man-for-himself individualism.” If this were true, it would, in my eyes, be a violation of scientific principles. Even if every known society has followed a certain practice (for instance, eating meat), and even if we can find evolutionary roots for this practice, it would not follow that this practice is morally defensible or practically desirable in our society. Indeed,, there is not a single paper or book that I authored or coauthored that drew any such political conclusions, or indeed any political conclusions at all. Nor am I aware of others who work in this tradition who have drawn such conclusions. Sociobiology is not liberal or conservative, or even middle of the road. It is just good science.
Some academic fields, including sociology, anthropology, and psychology, have no problem dealing with the fact that human beings are moral creatures, and that this morality is an important element in our success as a species. Others, including evolutionary and population biology, have had a harder time with this fact, because they have over the years developed theories that appear to show that evolutionarily fit behavior is necessarily selfish behavior. However, the moral nature of human society, and the key role of morality in our success as a species, can be accommodated without requiring evolutionary biology to abandon its cherished accomplishments. The selfish gene versus group selection issue, when properly formulated, has little to do with the nature of human sociality.
 Proceedings of the National Academy of Sciences 108,32 2011.