EVOLUTION AND ETHICS Ethics is the branch of philosophy that inquires into the nature of moral judgments and the basis for rules of conduct. It centers around the questions of what constitutes the good life and how it might be achieved. As philosophy, ethics involves the construction of ideal systems for making moral judgments based on principles (normative ethics), or analysis of the logic behind the presuppositions of normative ethics (analytical ethics or meta-ethics). Study of the actual ethical behavior of individuals or the standards held by entire cultures is called descriptive ethics which lies in the province of the social sciences, not philosophy. The difference between actual and ideal ethical behavior ("what is" as distinct from "what ought to be") separates science from philosophy in the area of ethics. In discussing the relationship between evolution and ethics we will examine three issues: the extent to which a knowledge of evolutionary biology can inform ethical thinking, the problem of free will in a determinist approach to scientific knowledge, and the origin of a human moral sense which allows moral behavior. Ethics and an Evolutionary Perspective Darwin's great contribution to the intellectual development of our culture was the idea that species are mutable. So radical is this departure from previous thinking that it is called the Darwinian revolution ( a paradigmatic shift comparable to the Copernican revolution) whose full implications have yet to be explored. We will note some of its philosophical ramifications below, but in so doing will only scratch the surface of how this dynamic worldview might alter our past static-world thinking. Human nature Normative ethics attempts to set up rules of conduct which apply to all humans and therefore is a form of ethical absolutism as opposed to systems restricted to particular cultures (ethical relativism). Normative ethics is based on natural law theory which states that what is good can be determined from an analysis of human nature. Rules of ethical conduct should be based on natural law, understood from an analysis of human nature, and not on positive law constructed from human consensus. For the ancient Greek philosophers, human nature was eternal (no beginning and no end) and immutable. Although individual humans varied, they all shared a common essence which resided in the human soul - more specifically in the rational soul's faculties of intellect and will. Through our intellect we could reason to the end or purpose of human existence and also understand what is good to achieve this end. Through our faculty of free will we could choose goods as means to our final end. Aristotle believed that the highest good was happiness and that virtues, e.g., prudence, temperance, fortitude and justice, were dispositions developed as means to attain happiness. Humans possessed characteristics of both the gods (in our rational soul) and animals (in our irrational soul). Since the gods lived a life of contemplation, humans should aspire to be like the gods rather than like animals whose behavior is dominated by emotions, pleasure and pain. Aristotle concluded that we should seek happiness in contemplation, not in pleasure. St. Thomas Aquinas adopted Aristotle's ethics with modification. Aquinas saw human nature as immutable but created by God, and agreed that the final goal of human existence was to be found in happiness through sharing in the glory of God in the Beatific Vision after death. What is good for humans is determined by our understanding of God's purpose in creating us, which Aquinas maintained is known from natural law and revelation in the Bible. Although ethics is a philosophical discipline, it is easy to see how moral theology can inform ethics regarding our final end and why over history religion has been closely allied with ethics. What does modern evolutionary biology have to say about human nature and the meaning of human existence? From an evolutionary perspective there is no such thing as a common nature shared by all humans and since evolution is a blind, opportunistic process, there is no purpose or meaning to human existence. Although the concept of evolution has a long history, its mechanistic basis has only recently been understood. Only when the essentialism (typology) of the ancient Greeks was replaced by population thinking was substantial progress made in understanding the mechanism behind evolution. Plato, as you recall, viewed species as eternal and distinct in an immutable essence shared by all individuals of the species. He dismissed individual variation as "accidental" and concentrated on the "substantial" characteristics which defined the species. For example, horses come in a variety of shapes, sizes and colors, but they all share the common essence of "horseness" - otherwise we would not recognize them as horses. Translated into practical taxonomy, this typological concept of species forced taxonomists to seek some commonality among the individuals they classified as belonging to the same species and so describe the species on the basis of this limited set of arbitrarily selected characteristics (taxonomic characters). In 1940 the Harvard systematist, Ernst Mayr, long an opponent of essentialism, developed the biological species concept which views species as variable over time and space, defined not by a common essence, but rather by the ability to interbreed. For Mayr, species are not absolute units to be defined by a set of essential taxonomic characters as the typological species concept holds, and individual variation is not an "accidental" phenomenon to be dismissed; rather, species are dynamic entities and variation is the key to understanding how they change over space and time. David L. Hull, a noted philosopher of biology, does not abandon essentialism in viewing the category species but does allow that at least part of the essence of species is variability. Hull argues that there is no human nature from an evolutionary perspective because species characteristics not only vary among individuals at any one time, but also over time. No matter what human characteristic you choose, you will find genetically-based individual variation subject to change over time. Thus, even if you were to define human nature in a statistical sense during some arbitrarily selected time, that nature would eventually change. Human equality is a political, philosophical and religious concept with no grounding in biological reality. It is not surprising therefore that biologists are so fascinated with individual variation. The one universal lesson that evolutionary biology teaches is that in sexually reproducing species no two individuals are exactly alike. The ramifications of this lesson must be considered by philosophers. E. O. Wilson, the founder of sociobiology, sees human nature as a set of genetically-based tendencies specified by culture. For Wilson human nature is grounded in the evolution of the brain which predisposes us to think in certain ways and this commonality exists in crosscultural universals, e.g., fear of strangers, incest taboo and nepotism. We are what we are because natural selection has acted on our genes to produce an adaptive response to the environment in which our ancestral hunter-gatherer ancestors lived, and we carry their genes into a modern environment quite different from the natural environment in which we evolved. Because biological evolution is slow relative to cultural evolution, these responses need not be adaptive today. We have no meaning or purpose built into us by our genes, other than to improve fitness, and must direct our future by choosing which of these biological imperatives inherited from our ancestors we wish to follow. We now have the capacity to alter our nature through genetic engineering and this poses an even more complex dilemma - what kind of a nature should we choose and who will do the choosing? Science can explain the "what is" of reality, but we must choose the "what ought to be." Science does not provide us with meaning and value; these come from our philosophical and religious traditions. There is no question, however, that a dynamic worldview has severely challenged the classical-medieval concept of human nature and natural law theory based on a static worldview. Evolutionary ethics Ever since Darwin, some scientists and philosophers have attempted to base ethics on evolutionary theory. This trend started with Herbert Spencer's Social Darwinism and continues today in the writings of Edward O. Wilson. Social Darwinism attempted to justify capitalist exploitation of workers by using natural selection theory erroneously - "survival of the fittest" rather than cooperation as the result of natural selection acting on humans. Wilson argues that our emotions (love, fear, hate, etc.) so influence our standards of good and evil that ethics should be "biologicized" and removed from the field of philosophy. While he stops short of claiming that we have genes for ethics, he does suggest that our goals are thrust upon us by genetic tendencies and that our thought patterns, rooted in the development of the brain, predispose us to behave ethically. In 1959 Julian S. Huxley presented his "evolutionary vision" as the keynote address at the University of Chicago's Centennial celebration of Darwin's On the Origin of Species. Huxley argued that our goals as a species should be based on the perspective of evolution and that our "destiny is to be the sole agent for the future evolution of this planet." Accordingly, our values must develop in the light of an evolutionary vision which seeks human improvement through scientific knowledge rather than "fixed dogma or ancient authority." Our outlook should be global rather than national, emphasize the quality and diversity of human life rather than quantity and uniformity, and seek individual personal development by abandoning the "democratic myth of equality ... 'free but unequal' should be our motto, and diversity of excellence, not conforming normalcy or mere adjustment, should be the aim of education." Huxley pointed to the problems of overpopulation, threat of a superscientific war using nuclear, chemical and biological weapons, the erosion of cultural diversity, the spread of Communist ideology, the failure to admit China into the United Nations, "our general preoccupation with means rather than ends, with technology and quantity rather than creativity and quality" and the increasing gap between the developed and underdeveloped nations of the world as major challenges which must be confronted if we are to assume our evolutionary destiny. Admirable, albeit somewhat controversial, ideas but flawed because they rest on the premise that our values should be based on scientific knowledge. Attempts to develop ethical systems based on an understanding of the process and product of evolution have never gained acceptance for two reasons: (1) they commit the naturalistic fallacy and (2) lack of general support for any standards derived from evolutionary principles. The naturalistic fallacy is a name given in 1903 by G. E. Moore to a principle developed by the Scottish philosopher David Hume (1711-1776) which denies legitimacy to any attempt to define good in terms of natural objects, or to deduce values from facts. One commits the naturalistic fallacy when one argues from "what is" to "what ought to be." Value or "ought to be" conclusions can logically only be drawn from normative or "ought to be" premises, not from empirical facts. Thus, for example, it is valid to conclude that the killing of whales ought to be limited from the premise: humans ought to preserve natural resources, but not from the premise: whales are endangered species. The "what is" of reality is not a philosophical justification for "what ought to be." Science attempts to describe "what is" and so the findings of science provide no basis for setting ethical norms. Stephen Jay Gould expressed this same idea in another manner when he noted that there are no moral messages in nature. We know that aged and infirm tigers will turn to preying upon humans because we are easier to capture than other animals. We cannot conclude from this observation that aged tigers ought to be fed humans. Likewise, any attempt to define "what ought to be" from a knowledge of evolution commits the naturalistic fallacy. Evolutionary generalities have in themselves no moral force. If we were to grant that all life is good because it is the product of evolution (and in so doing commit the naturalistic fallacy), would that be sufficient justification for proscribing the planned extinction of certain species, e.g., pathogenic bacteria? Would any physician consider immunological vaccines immoral? One should not conclude from Hume's law or the "is-ought" distinction that normative ethics should totally disregard the findings of science. It would be foolhardy to develop ethical norms which direct behavior contrary to the way nature operates. To do so could not only lead to misery and death, but could also threaten the continued existence of our species. The naturalistic fallacy simply points out that ethical norms should be derived from well-reasoned ethical principles, not simply from scientific facts. Agreement between facts and values is possible through ethical reasoning, not because facts in themselves constitute values. Even if we were to assume that facts were values, evolution would not serve as a basis for developing ethical norms. There are no universally accepted evolutionary facts or theories which could serve as a basis for normative ethics. If natural selection operating to produce selfishness were taken as a basis for normative ethics, as was the case in Social Darwinism, it could be legitimately argued that natural selection also produces cooperation and that alternative forms of selection could produce altruistic behavior. There is no question that natural selection can favor selfish behavior, but natural selection is only one facet of modern evolutionary theory and is opposed by competing hypotheses within the evolutionary paradigm. None of the different hypotheses, which together comprise the richness of evolutionary theory, are universal enough to serve as the basis for normative judgments. Since evolution hardly provides a firm foundation for absolute ethical claims, philosophers have routinely rejected all attempts to develop an evolutionary ethic. Normative ethical claims should be absolute and binding on all humans. They should be based on what we think human nature, meaning and destiny ought to be. It makes little difference that there may in fact be no such thing as a human nature. We alone have the ability to reason and project into the future the consequences of our actions. Ethics emanates from our culture, not from our genes. How we see ourselves will be informed by reason and faith which will furnish the goods that we seek as both the end and means of our destiny. Science will assist us by providing insight into limits and possible consequences of our actions, but will not by itself set the values that will guide our destiny. Failure to heed the lessons of evolutionary science and a dynamic world- view in setting our goals, however, could turn out to be disastrous. Determinism and Free Will Ethics is based on the concept of free will: to be morally responsible for one's action requires the capacity to choose freely among alternative courses of action. This being the case, does evolutionary theory, based as it is on genetics, allow for individual freedom? The foundation of science is the assumption that the universe is orderly and follows laws which are knowable: every effect must have a cause. The goal of scientists is to explain the physical cause of natural effects; hence, science is based on the principle of determinism. Causal (determinist) laws specify the conditions under which an effect will result: if the conditions obtain, then the result will follow. Due to individual variation and the complexity of organization studied in biology, determinist models have given way to more indeterminist (stochastic) ones which explain effects in terms of probabilities rather than fixed outcomes. The course of evolution cannot be determined due to lack of information regarding future levels of genetic variation and environmental factors that might act as selective pressures. Furthermore, chance effects (which occur through mutation, sexual reproduction and genetic drift) add to uncertainty about the future. We say something occurs through chance if we don't know its precise cause, thus chance might be a function of imperfect knowledge rather than indeterminism. A scientific approach to explaining human behavior will necessarily have a determinist flavor. Is human behavior sufficiently undetermined to allow freedom of choice in moral matters, or is free will only an illusion in a determined universe? One answer to this question is to assert free will and deny human determinism. Humans, under this indeterminist view, are moral agents capable of choosing between right and wrong alternatives. Consequently, moral agents are responsible for their actions. This position maintains that determinism and free will are incompatible and so denies determinism in the area of morality. Can moral choice be reconciled with determinism? For hard determinists the answer is no, but soft determinists claim that individuals can exercise choice even though their acts are determined. Both kinds of determinists hold that specific acts are caused, i.e., have sufficient conditions which explain them. Soft determinists maintain that when acts are avoidable, the individual exercises a choice and so is morally responsible for the act. For the soft determinist, the moral agent's decision, freely made, is one of the sufficient conditions that specifies the agent's behavior. Hard determinists reject this concept by claiming that, although the act may be avoidable, the choice is not; it is determined by causes operating in the individual's past history. For the hard determinist, free will is only an illusion. For the soft determinist, free will exists even though acts are determined. Michael Ruse, a philosopher of biology and a soft determinist, argues that free will requires causal determinism; if not, individuals could neither be praised nor blamed for their behavior. Causal determinism, however, does not imply control determinism. In summary, there are three basic positions regarding individual freedom and moral responsibility: 1. Indeterminist position - neither the act nor the moral agent is determined; free will is a reality and the agent is morally responsible for the act. 2. Soft determinist position - the act is determined but the choice between alternatives is not; the moral agent chooses freely and is morally responsible for the act. The choice itself, however, is one of the determining factors or causes of the act. 3. Hard determinist position - both the act and the moral agent are determined; there is no free will and no moral responsibility for the act. Origin of Our Moral Sense Morality itself is cultural in origin for it refers to values and codes of conduct deemed moral by some normative criterion. Our ability to behave morally is based on a moral sense, involving a concern for others and sense of right and wrong, without which no moral system could exist. How might this concern for others have arisen? A number of explanations are possible. One, consistent with a static worldview and the indeterminist position regarding human moral behavior, is that our moral sense is built into human nature (our conscience) and either is eternal (Aristotle's view) or was created by God (Christian moral theology). This explanation must be accepted on faith since it is totally outside the purview of science which attempts to explain natural phenomena mechanistically. Can science provide any insight into the origin of our moral sense? More specifically, can evolutionary theoy fact that every human categorizes acts as right or wrong, and that we all have a conscience which leads to feelings of guilt? Some have suggested that our moral sense is the product of culture, i.e., we are taught to be concerned for others. The difficulty with this suggestion is that culture itself is the product of human society which can exist only if individuals in society already have some concern for others. Culture does influence human behavior and some anthropologists, e.g., Leslie White, have suggested that it is the determining factor in human behavior and exists apart from us as some superorganismic force. If so, how did culture arise if not through the agency of human behavior? If we originally had no concern for others, then we never would have cooperated to the extent that culture could evolve to act as a determinant of human behavior. It seems therefore that our moral sense predated the development of culture; hence, our concern for others seems not to have arisen through cultural or psychosocial evolution. Different theories within the framework of biological or organic evolution offer possible explanations for the origin of our moral sense and these are outlined below. 1. Our moral sense evolved through the agency of natural selection. We normally think of natural selection as favoring the evolution of selfish behavior, but cooperative behavior (enlightened self-interest) will evolve through natural selection if the benefits outweigh the costs in terms of individual reproductive success. The evolution of reciprocity (reciprocal altruism) could account for our concern for others because helping others results in a later payback to the altruist (direct reciprocity). If the payback is to a relative of the altruist or betters the society in which the altruist lives, a concern for others could evolve through indirect reci- procity. Through either direct or indirect reciprocity, both of which are the product of natural selection, we could have evolved a genetically-based tendency to behave ethically. Psychotherapists find that some psychological stress experienced by people today stems from an inability to deal effectively with reciprocal agreements. Individuals suffer either from entitlement (they think they have given more than they have received) or guilt (they think they have received more than they have given). Thus reciprocal relationships play a major role in our society and the ability to think in these terms might well have a genetic root. 2. Our moral sense evolved through the agency of kin selection. Nepotism is a very common form of human altruism and benefits the altruist by maximizing inclusive fitness. Concern for the well being of relatives could have played a vital role in human survival when human population density was low and societies were largely, if not exclusively, extended families consisting of genetically related individuals. As group size increased, nonrelatives could have been treated as if they were relatives (the idea of "blood brothers" bonded by a ritualized exchange of blood) and so a genetically-mediated tendency to be concerned for relatives could have been broadened culturally to include non- relatives. The fact that kinship ties are an important part of all societies supports this hypothesis. 3. Our moral sense evolved through the agency of group selection. A concern for others acts to benefit society at large and so could have evolved by means of group selection. If groups which exhibited this concern outlasted those that didn't, a species-specific moral sense could have evolved. This explanation was favored by Darwin who admitted that selfishness promoted by natural selection would present some difficulty in explaining the evolution of moral systems. That a central focus of ethics is the "common good" lends support to this explanation. 4. Our moral sense evolved as a nonadaptive con- sequence of natural or species selection, or by means of genetic drift. All of the three explanations advanced above posit that our moral sense has some adaptive value. This fourth explanation argues that it is nonadaptive. Non- adaptive features of the phenotype could be carried along during evolution by selection of genes which also produce adaptive traits. Thus, if the gene is selected for its positive contri- bution to the phenotype, the other traits it influences, even if nonadaptive or maladaptive, will also be selected. You will recall that this is one argument advanced to explain the role of selection in producing a postmating RIM in an allopatric population. Alternatively, some traits which confer no adaptive benefits upon individuals could be carried along during phylogeny by species selection, or result from genetic drift operating during the processes of speciation (the founder effect) or phyletic evolution in small populations. In essence this explanation suggests that our moral sense evolved as a result of chance rather than of direction. In 1987 the sociobiologist Richard Alexander published a book entitled The Biology of Moral Systems in which he argues that our morality evolved due to indirect reciprocity. He suggests that intergroup warfare was a powerful force shaping our culture and the larger the group, the greater was its advantage over neighboring groups. To hold large groups together reciprocal agreements (positive law) were reached by negotiation and that such indirect reciprocity produced our moral systems. More recently, the anthropologist William Irons, in a critique of this theory, has suggested predictions whereby Alexander's theory can be tested. Thus, modern evolutionary scientists (both biological and social) are attempting to explore moral behavior from an evolutionary perspective and so touch upon subjects previously thought to reside solely in the domains of philosophy and theology. The explanation of human existence and our unique ethical behavior advanced by classical-medieval thinking is now giving way to a far more complicated analysis based on the concept of human evolution. No definitive answers yet exist, but an evolutionary interpretation of the human condition promises to shed light on areas of inquiry previously considered beyond the reach of science. The better we understand our past and the forces which shaped us, the better will be our prospects for beating the odds which favor our extinction. Science will not produce the values which might ensure our future; these will come from philosophy and religion which posit meaning and purpose to our existence. Science can, however, provide insight into our potentials and limitations and provide the setting for developing values that will guide us on our evolutionary journey. These are exciting times as the old static worldview is being challenged by the newer dynamic and evolutionary perspective. Given this current state of innovation, controversy and confusion, it is not surprising that some people have resolved these problems by affirming the truth of past tradition and denying evolution. These are the scientific creationists who posit that "kinds" are immutable and that the principles of microevolution, while explaining change within "kinds", provide no basis for believing that one "kind" can change into, or give rise to, another over time. Their views are the subject of our next discussion.