Processing Towards Life

by L. Charles Birch

Charles Birch is a biologist specializing in genetics, and resides in Australia. He is joint winner of the 1990 International Templeton Prize for Progress in Religion.. His teaching career includes Oxford, Columbia and the Universities of Chicago and Minnesota, as well as visiting professor of genetics at the University of California at Berkeley and professor of biology at the University of Sydney. Professor Birch has blazed new paths into the relationships between science and faith.

The following article appeared in Process Studies, pp. 280-291, Volume 27, Number 3-4, Fall-Winter, 1998. Process Studies is published quarterly by the Center for Process Studies, 1325 N. College Ave., Claremont, CA 91711. Used by permission. This material was prepared for Religion Online by Ted and Winnie Brock.

SUMMARY

Subjective aspects of life such as consciousness, purpose and free will are either ignored or else attempts are made to reduce the subjective to the objective. The author suggests the laws of self organization help explain the sources of order in cosmic evolution including the origin of life.

Bertrand Russell said that either life is matter-like or matter is life-like. A proposition of process thought is that matter is life-like. The proposition that life is matter-like leads to the traditional reductionist analysis of living organisms that goes on in biological laboratories. The ultimate apotheosis of this approach is molecular biology. Reductionist analyses are analyses of the objective aspects of living organisms such as the conduction of electrical impulses in nerves or the biochemistry of the formation of blood. As a methodology, reductionism is justifiable provided due recognition is given to its limitations.

In contemporary biology subjective aspects of life such as consciousness, purpose and free will are either ignored or else attempts are made to reduce the subjective to the objective. Instead we can take another approach as described by Mary Midgley: "There are two points of view -- inside and outside, subjective and objective, the patient’s point of view on his toothache and that of the dentist who studies it" (OW 508).

The concept of "the patient’s point of view," which is its own experience, applies all down the line from people to protons in process thought. Processing towards life is my metaphor for cosmic evolution from a relatively undifferentiated universe right after the big bang, for example a universe consisting of hydrogen atoms only. It seems to me that Whitehead’s two lectures entitled "Nature and Life" (in MT) delivered at The University of Chicago were essentially saying that an understanding of cosmic evolution had to be informed by a concept of what life is. The concept of what life is proposes that the individual entities of existence, or "the really real things (which) compose the evolving universe" (MT 151), are occasions of experience.

In the universe that consisted of hydrogen atoms alone, the sum total of occasions of experience must have been minimal in cosmic history. The internal relations of that universe must have been minimal compared with a universe that has in it plants and animals including us. What has happened in between a universe of hydrogen and us?

One aspect of the story is told by scientists in their account of cosmic and biological evolution. This is an account of the evolution of (what they see as) objects. Individual organisms are investigated as if they were machines, devoid of self-determination or spontaneity in any sense and so subject only to external forces. They are objects, not subjects. Are there any leads from the world of science of today suggesting that the individual entities of creation from protons to people are not simply objects pushed around by external forces? There is one, I suggest, that arises from what is called complexity theory. It proposes that sufficiently large systems of parts with enough interactions will generate totally new, but simple, laws of self-organization that help to explain what has happened in evolution.

I. Self-organization in Cosmic and Biological Evolution

Physicists and cosmologists regard self-organization as the source of order in cosmic evolution up to and including the origin of life. Some of them, notably Paul Davies, have said that the onus is now on biologists to demonstrate the importance of self-organization in biological evolution. An example of what is meant by self-organization from physics is the formation of the myriad symmetrical shapes of snowflakes. Probably no two snowflakes are alike. Snowflakes are formed by crystals of ice that generally have a hexagonal pattern. Often the pattern is beautifully intricate. The size and shape of a snowflake depends mainly on temperature and the amount of water vapor available as they form. The details of the design are dependent upon the environment in which the snowflake forms. In all this physical forces are involved, pushing atoms of water this way and that.

Many simple physical systems exhibit spontaneous order of this sort. An oil droplet in water forms a sphere. Lipids in water form hollow bilipid membrane spheres, such as cell membranes. Further examples of self-organization in physics are given by Paul Davies (CB 72-92). The question I now put and leave as a question for the moment is this: is anything else going on in the self-organization of snow flakes and the self-organization of hydrogen atoms that led to the universe and us?

But first consider some examples of self-organization in biology at different levels of organization. It seems likely that the self-repeating patterns generated by growth processes of plants that result in the symmetry of a sunflower or a pine cone are best understood in terms of self-organization. The spiral rows of scales in a pine cone conform, in their mathematical arrangement, to the famous Fibonacci series of numbers (RU 151). A simple virus, such as the tobacco mosaic virus, forms by self-assembly in which all the participating proteins are organized into a complexly structured virus. If the parts of these viruses are disassembled they spontaneously reassemble. More complex viruses cannot do this (see VA). Another example of self-organization at the molecular level is the local interaction among amino acids which give rise to complexly folded protein molecules. When the complex protein molecule is dissociated from a three dimensional state to a simpler linear state, it is followed by spontaneous reassembly. They are not always able to so self-organize without guidance from the charmingly named chaperone proteins that guide the three dimensional folding of proteins.

Spontaneous self-organization is invoked by biochemists in the evolution of the prebiotic world in which a variety of atoms assembled into organic molecules eventually giving rise to molecules of RNA, DNA and proteins which led to further complex assemblies and eventually to cells. Manfred Eigen coined the term "molecular self-organization" to describe molecular evolution that could have given rise to the origin of life. A summary of some of these processes is given by Fritjof Capra (WOL 75-150). Kauffman sees the origin of life not as an incalculably improbable accident but as "an expected fulfillment of the natural order" as a result of the phenomenon of self-organization (HU 20). Most of Kauffman’s long book deals with mathematical models and some biochemical models of "non-equilibrium ordered systems that lead to spontaneous self-organization into more complex structures. The universe soon after the Big Bang consisted of only one sort of entity -- hydrogen. Today the living world consists of at least ten million different small organic molecules and at least one trillion different proteins. Where did all this diversity come from (HU 115)? Kauffman’s book is devoted to answering this question in terms of the principle of self-organization.

Until recently self-organization had been little recognized in more complex entities. All the examples which follow were, until recently, interpreted in terms of centralized organization. However, recent studies provide evidence that in each of the following examples the order is a consequence of self-organization and not centralized organization. The evidence is given in each case.

A notable example is the slime moulds that live in soil. Spores of slime moulds on germination produce amoeba-like cells. These cells immediately disperse as though mutually repelled from each other. Provided they have sufficient bacteria, which is their food in the soil, they divide like amoebae by simple fission. When food becomes scarce the amoeba-like cells tend to distribute themselves uniformly and no longer repel one another. Then they aggregate at a number of centers to form at each center a slug-like creature that slithers like a slug. It may reach a diameter of 25 centimeters or more. From this apparently undifferentiated mass of cells a stalk grows at the top of which a fruiting body is formed that develops spores. The fruiting body bursts to distribute its spores and so the strange life-cycle continues. What causes these changes? The present understanding is that a chemical substance called acrasin is secreted by the amoebae when they run out of food. The amoebae move up a gradient of acrasin resulting in their aggregation to form the slug. Many different species of slime mould may live in the same place. How is it then that the cells of the different species don’t get mixed up in aggregation? The answer is that different species secrete different acrasins. There is some evidence also that concentration waves of a chemical substance governs the production of the stalk and fruiting body. The effect of the concentration wave is to activate genes whose message is -- produce a fruiting body (see DIM and GSSA).

Resnick simulated the aggregation of slime mould cells in a computer model (LL 232-233). Each "creature" in his model is given the characteristic corresponding to the emission of a chemical substance while also following the gradient of this chemical substance. The chemical is given a finite life corresponding to its rate of evaporation. With this decentralized strategy the creatures’ aggregate into clusters on his computer screen.

With such examples in mind we can define self-organization as "patterns determined, not by some centralized authority, but by local interactions about decentralized components" (LL 229). It is a process of ordering from a less ordered state to a more ordered state. Self-organization is contrasted with centralized organization, such, or example, as the production of order by DNA in the cell. This has led to the classical model that evolution is change in the organizing molecules of DNA and RNA. So we can recognize two forms of organization in living organisms, self-organization and centralized organization.

Other examples of self-organization in biology have been investigated such, for example, as the construction of a termite nest with its complex chambers. Termites construct their complex nests in an orderly fashion that, at least in part, is guided by chemical gradients. Termites are among the master architects of the animal world. When a termite deposits a lump of earth on the base of the forthcoming nest it deposits at the same time a chemical that attracts other termites to the same place to deposit their lumps of earth there and so form a pillar. That is but one aspect of the building of a complexly structured nest by a large number of individual termites cooperating together. Each termite colony has a queen (OC 186). But, as in ant colonies, the queen does not "tell" the termites what to do. The queen is more like a mother than a ruling queen. There is no one in charge of a master plan. Rather, each termite carries out a relatively simple task. Termites are practically blind, so they must interact with each other and the world around them primarily through the senses of touch and smell. From local interactions among thousands of termites impressive structures emerge.

Resnick has made computer models of some of the steps in the construction of a termite nest (LL 234). As he points out, the construction of an entire termite nest would be a monumental project. Instead, he proceeded with a simple model to program termites to collect wood chips and put them in piles. At the start of the program wood chips were scattered randomly throughout the termites world. The challenge was to make the termites organize the wood chips into a few orderly piles. He made each individual termite obey the following rules:

The program worked. At first the termites gathered the wood chips into hundreds of small piles, but gradually the number of piles declined while the number of wood chips in surviving piles increased.

AntFarm is a computer program that simulates the foraging strategies of ants (FC 248 -251). Many ants obeying simple rules produce the complex foraging behavior. Self-organizing ants require just four rules to be followed:

Another striking example of self-organization in animal behavior is the swarm-raid of the army ant (AA 139-145). A raid consists of a dense phalanx of up to 200,000 workers that march relentlessly across the forest floor. The raiders can be up to 20 meters wide. It leaves in its wake not only a trail of carnage but also a series of connected columns along which the victorious army ant workers run with their booty. These columns all lead to the principal trail of the raid, which links the swarm front to the temporary bivouac. It is inconceivable that a tiny individual within the 200 meter long raid has any knowledge of the plan of the raid as a whole. The structure of the swarm can be achieved by simple, self-organizing interactions among the raiding ants. Franks (AA) devised computer simulations in which moving ants lay down chemical trails which organize the movement patterns of other individuals throughout the developing raid. His simulations mimic with some precision real raids. His models show how the collective behavior of the swarm can be achieved with no central coordination, but instead through the communication between foragers by the laying down of, and reaction to, trail chemicals.

In colonies of social insects, workers perform a variety of tasks such as foraging, brood care and nest construction. As the needs of the colony change, and as resources become available, colonies adjust the numbers of workers engaged in each task. Task allocation is the process that results in specific workers being engaged in specific tasks in numbers appropriate to the current situation. Until the mid-1980s, research emphasized the internal factors within an individual that determine its task. Internal factors had to do with body size, age and genetic constitution. However, in recent years it has become evident that division of labor had more to do with environment and that it is rare for individuals to specialize in particular tasks throughout their lives. From day to day or even hour to hour an individual worker may perform a variety of tasks, changing its task as circumstances require. For example, a honey bee forager’s decision whether to collect nectar or remain in the nest depends on how much nectar is already stored in the nest (OWSI). As a result of investigating such phenomena Deborah Gordon makes the following assessment of what is happening:

There is, in the above quotation, the important suggestion that self-organization may help to elucidate one of the most complex ordering processes, as yet little understood, in living organisms, namely development from egg to adult. The initial single cell of the egg undergoes a number of cell divisions to produce a mass of similar cells. At some subsequent stage differentiation of these cells proceed as they multiply further. Some become muscle cells, others nerve cells, and so on. All coordinate to become a unitary organism of millions of cells with a body plan that is different for different organisms. Muscle cells are different from nerve cells, not because they have different genes; their genes are the same. However, different genes are switched on in different environments. How the appropriate genes are switched on in appropriate places remains a problem. One proposal involves chemical gradients. For example in the fruit fly the first difference between the front and back end of the egg is caused by the cells of the mother’s ovary, external to the egg, that release at the anterior end a specific chemical which then diffuses backwards, giving rise to a chemical gradient of concentration. This in turn could cause different genes to be switched on in different places. A single gradient cannot set up a whole pattern, but a succession of such processes might. We know that chemical gradients are involved in the ordering of the building of a termite nest and in the life history of slime moulds. It is possible that in embryonic development similar sorts of ordering are at least initiated by chemical gradients (see LEC).

Self-organization is part of the research program of so called complexity theory at the Santa Fe Institute for the Study of Complex Systems. The approach of the workers in this institute is highly theoretical. As Lewontin had remarked, complexity theory "proposes that sufficiently large systems of parts with enough interaction will generate totally new, but simple ‘laws of organization’ that will explain, among other things, us" (LN 26). The behavior of these models turns out to be what are, in the mathematical sense, chaotic. Kauffman (in OO) argues that chaotic systems can give rise to structures "for free," instead of each detail of structure having been forged independently by natural selection. According to his interpretation of his models the system leaps spontaneously into a state of greater organized complexity. This is what Kauffman calls self-organization. The devotees of this approach have been criticized by geneticists and evolutionists as practicing "fact-free" science in contrast to ordinary "earth-bound" genetics (see OE and LEC). It is a question for the future as to whether or not Kauffman’s models will be heuristically valuable for biology.

All the examples I have given of self-organization in biology are explained by biologists in strictly mechanistic terms, complex though these mechanisms usually are. Some of the processes can be replicated to some extent on a computer. But this does not necessarily imply that the behaving entities are in all respects machines. This is the subject of the sections which follow.

II. Self-organization and Internal Relations

Self-organization is exactly what we might expect of Whiteheadian individual entities. Each individual entity, be it a proton, a protein molecule, an amoeba of a slime mould or an ant in an army raid can be regarded in the Whiteheadian scheme as being what it is largely by virtue of its internal relations to its environment, be those components of environment temperature for a snowflake, acrasin for an amoeba or a neighbor ant for another ant. Each entity is then seen as a subject relating internally to its environment. Each is having experiences, unconscious though they may be. Individual entities conform to Charles Kingsley’s proposition in his novel "The Water Babies" that God makes things that make themselves. In Whiteheadian terms God is not responsible unilaterally for what happens. God and the entities of the world are co-creators.

The Whiteheadian interpretation of self-organizing entities is in contrast to the parts that make up a machine. He enunciated more clearly than anyone how creative evolution of living organisms cannot be understood if the elements composing them are conceived as individual entities that maintain exactly their identity throughout all the changes and interactions, as is the case with the parts of a machine. That is the Newtonian model of the universe. Complex living organisms can be broken down into their component parts such as their cells. How is it that the whole has properties the components do not have? It is evident that the properties of the whole are not found in the parts, except as they are organized in the whole. It is for this reason that the reductionist program of science is deficient. One response has been to say that the whole is more than the sum of its parts. There is an element of truth in this statement, but it does not go far enough. It is not just that the whole is more than the sum of its parts. It is that parts become qualitatively different by being parts of a whole. Lewontin, Rose and Kamin discuss the different levels at which atoms assemble to make molecules, molecules assemble to make cells and so on: "as one moves up a level the properties of each larger whole are given not merely by the units of which it is composed but of the organizing relations between them ... these organizing relationships mean that the properties of matter relevant at one level are just inapplicable at other levels" (NG 278).

In the process perspective, cosmic and biological evolution are not simply the evolution of objects that are reorganized by change in their external relations but change in internal relations of subjects. It is the evolution of subjects. A subject is an individual entity that has a degree of self-determination. It has some degree of mentality that is presumably minuscule in the proton compared to the person. Of course we don’t know what it is like to be a proton or an electron and to have its subjective experience of being what it is. Sir J.J. Thompson, who discovered the electron in 1897, said that to know what an electron is you would have to be one. Complete knowledge is complete possession. He was making the distinction between knowing something from within and something from without. The only individual entity that we know from within is ourselves. We can only infer the within of other individual entities. The important point is that mentality is not just in a corner of nature. It is pervasive.

But you may ask -- at what point does life appear in the processing? The answer is -- at no point. For matter is life-like. The life-like process is tied up with novelty. Novelty is not mere change. The ever-present entropic tendency to decay is change. That tendency can be resisted in two ways. It can be resisted by the very stable structure of many aggregates such as rocks. These endure by countless repetition of unchanging patterns. It can be overcome locally by creative novelty which rises above external determination. Hence life is directed against the repetitious mechanism of the universe. There is an urge in life to meet life’s as yet unrealized possibilities.

"Life," says Whitehead, "is novelty of appetition" (PMO2). "The universe is creative advance into novelty" (PR 222).

III. Progress in Evolution?

The fundamental question to ask about cosmic evolution is why the universe that at one time consisted of hydrogen atoms and nothing else didn’t just stay that way? Why go on to other sorts of atoms, complex molecules, cells and countless species of plants and animals? The Whiteheadian proposition is that on the one hand the individual entities themselves at any stage have a propensity for creativity and that this urge is met by the potentiality of the universe from its foundations for all sorts of possibilities to be realized. Lure is met by urge of the creature.

The Whiteheadian perspective appears to be counter to an emphasis by some biologists, notably that of Stephen J. Gould, in their interpretation of biological evolution. "Natural evolution," says Gould, "includes no principle of predictable progress or movement to greater complexity" (LG 222). Since complexity of organization has frequently been used as a measure of progress in evolution Gould equates progress with complexity. There is no inevitability, says Gould, that there will be an increase in complexity with time. Bacteria must have been amongst the earliest organisms to evolve some billions of years ago. And they haven’t changed much. They do what they do pretty well and there are more of them, both in kind and numbers, than of any other sort of organism. There is no law that says they have to change. "The Age of Bacteria," argues Gould, was an age that persisted for billions of years from near the beginning right up to now. Bacteria alone formed the tree of life for the first 2 billion years, about half of life’s full history. We still live in the "Age of Bacteria" Bacteria are a classic example of persistence with little change. Other organisms have changed from a complex state to a less complex one. Many intestinal parasites have lost most of their organs to become simple sacs with few organs to deal with reproduction and the digested nutrients they absorb from the intestine of their host. They have lost rather than gained complexity.

There are, of course, other sequences of evolution which can be regarded as progressive trends in complexity such as the increase in size of the brain of Homo over the last two million years. But there is no law that says the brain must go on increasing in size. It has got to a point where it seems to be doing a pretty good job in enabling humans to survive, provided we don’t decide to destroy ourselves. Trends continue while they have adaptive value for the organism as a consequence of natural selection. The history of biological evolution is also the history of dead ends such as the dinosaurs. The tree of life is not like a single ladder with bacteria on the bottom rung and humans on the top with increasing complexity in between. It is more like a tree with a myriad of branches, many of them dead ones. Most of the species that have ever existed are extinct. Indeed it is the fate of all species to become extinct.

While simple forms dominate in most environments Gould concedes that there is an increase in complexity of the most complex organisms and that human beings are probably more complex than anything that preceded them. But he adds, "I fervently deny that this limited fact can provide an argument for general progress as a defining thrust of life’s history" (LG 169). His reason for saying this is that if you look at organisms, not just at the beginning, when life had its minimal complexity, but at any subsequent time in evolutionary history, there is no evidence that these organisms in the course of time led to more complex creatures. Some did, but sometimes the movement went in the opposite direction.

What seems to have happened in evolution is that every conceivable ecological niche gets occupied. If the occupants are simple bacteria and no one else can do the job as well, then there is no cause for them to be pushed out by more complex creatures. It might happen that a more complex organism might do the job better, in which case they would probably invade the niche. Or an even less complex organism may invade the niche. In this sense every step in the evolution of a new organism (be it an increase or decrease in complexity) is in Whitehead’s terminology "a creative advance into novelty" (PR 222).

Gould’s argument has the merit that it warns us not to be too simplistic about attributing trends in evolution. Yet none of what he says is counter to the proposition that every creature has its inborn propensity to survive and reproduce. This can be measured in objective terms of survival and reproduction and biologists do just that. But the principle can be interpreted subjectively, as Whitehead does in terms of an urge to live (FR 8). Human beings, for example, experience an urge toward novelty of experience and more satisfying experience. When it disappears the quality of human life and even life’s physical manifestations cease to exist. The same subjective principle can be applied to other organisms, be they simple bacteria, dinosaurs or cats and dogs. Evolutionary biologists for the most part deal with living organisms as objects and not as subjects, so it is not altogether surprising that they do not take account of the subjective. To so take account is not to invoke some mystical force but to regard the subjective as real both in interpreting animal behavior (as Donald R. Griffin does in his book, Animal Minds) and as I am suggesting in interpreting evolution. So Whitehead wrote:

V. The Past, the Present and the Future

My understanding is that there are two elements in internal relations, be the actual entity a proton or a person or anything in between such as an army ant. One is that the entity has internal relations with its immediate past which we could call memory (Whitehead’s prehension). The other is that the entity has the aim of constituting its present occasion both for immediate "satisfaction" and for the sake of the anticipated possible future state. "Life," says Whitehead, "is the enjoyment of emotion derived from the past and aimed at the future" (MT 167). The past is a real cause, so too possibilities are real (final) causes. And so too are external or mechanical (efficient) causes.

The evolutionary history of life suggested to Whitehead that there is an ever present urge which can be interpreted as purposive. It can be seen as an aim to greater richness of experience or "higher modes of subjective satisfaction" (FR 8). This does not mean that every successive step in evolution involved an increase in richness of experience of the entity being evolved. It does mean that from the foundations of the universe there was the possibility (not the inevitability) of all sorts of experience, including self-conscious experience that we know in ourselves. For Whitehead the art of life is first to be alive, secondly to be alive in a satisfactory way, and thirdly to acquire an increase in satisfaction. We know how this is true of human life. The conduct of human affairs is dominated by our recognition of foresight determining purpose and purpose issuing in conduct. Whitehead comments that "Scientists animated by the purpose of proving that they are purposeless constitute an interesting subject for study" (FR 16).

In writing about purpose Whitehead was discussing not just human life but life in general. The extreme rejection of final causation from our categories of explanation has been fallacious. The "vacuous actualities" of classical physics cannot evolve. They can only be rearranged as substances. "On this theory," says Whitehead, "all that there is to be known is that inexplicable bits of matter are hurrying about with their motions correlated by inexplicable laws expressible in terms of their spatial relations to each other. If this be the final dogmatic truth, philosophy can have nothing to say to natural science" (FR 50). The process view is that each actual entity from protons to people are occasions of experience which is the outcome of its own purpose. As Charles Hartshorne says, "I believe that the most significant model we can have even of the simplest parts of the universe, say molecules, atoms, and particles, is that they are the simplest, most primitive cases of that which our own natures illustrate in vastly more complex and highly evolved forms" (WM 120).

In the process perspective, biological evolution is seen not just as involving mechanical changes say to the heart as a pump, but internal changes whereby the experience or internal relations becomes richer in a human being as compared with a mosquito. "Creativity,’ said Whitehead, "is the principle of novelty" (PR 21). What then is creatively novel about evolutionary change? There is novelty along the route in the sense that human experience is novel compared to the experience of a dinosaur. A world of dinosaurs without humans is a different world from one that contains humans. But human experience has a continuity in origin from the feelings that constituted the being of the first mammals, the reptiles from which they evolved and all individual entities prior to them in the evolutionary sequence going back to the physicists’ initially featureless universe -- hence Whitehead’s proposition that the cosmic evolution of the universe "is a creative advance into novelty" (PR 222). Something is achieved in the process. To call that something creative advance or novelty is less ambiguous and less misleading than the term progress.

There exists the counter tendency of entropy in which organization becomes less with the passage of time and the universe as we know it will no longer exist. This is a reason why we need in addition to a processing toward life a processing toward death which has to do with the saving of what has been achieved in cosmic evolution, despite the death of the universe as we know it. These two become one coherent concept in the Whiteheadian scheme in which God not only persuades the world but experiences the world as it is made. God is different because of all that has been created in cosmic and biological evolution. So it is true to say that the universe would not be as it is if we had never been. At the end of the Russian Orthodox service for the dead, the choir and the mourners join together in saying "Viechnagu Pamjat." The words mean eternal memory. The memory in question is God’s. That is another story. It is a story that Whitehead calls the consequent nature of God.

References

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CB Paul Davies, The Cosmic Blueprint. London: Unwin Paperbacks, 1989.

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LG Stephen J. Gould, Life’s Grandeur. London: Jonathon Cape, 1996.

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LN Richard Lewontin, "The Last of the Nasties" New York Review of Books 43 (1996), 20-26.

NG R.C. Lewontin, Steven Rose, and Leon J. Kamin, Not in Our Genes: Biology, Ideology and Human Nature. New York: Pantheon, 1984.

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