Evolutionary Ethics
Evolutionary Ethics: Doing Philosophy Scientifically
Raivydas Simenas
Creighton University
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Evolutionary Ethics
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Evolutionary Ethics: Doing Philosophy Scientifically
Ethics is usually thought of as an esoteric discipline. Indeed, currently it is being
taught in philosophy departments, and its instructors usually analyze the works of
Aristotle, Kant, or John Stuart Mill. During the last few decades, however, a different
way of doing ethics has emerged, which emphasizes the importance of scientific theories
and primarily the theory of evolution. The basic concern of evolutionary ethicists is to
provide an explanation for our ethical intuitions. While in order to do so the traditional
ethics has invoked various implausible notions, such as objectively existing ethical facts
to which we have access through some kind of sixth sense (Moore, 1903), evolutionary
ethics draws its inspiration from the theory of evolution and game theoretical models to
find out about evolutionary stable patterns of behavior.
From Social Darwinism to Evolutionary Ethics
One of the landslide intellectual achievements of the 19th century, dealing a
major blow to the already weakening traditional worldview with its roots in the Bible, is
Charles Darwin’s On the Origin of Species, published in 1859. If up until then human
beings had been largely considered to occupy the central place in the world, Darwin
diminished the strict boundaries separating the species by advancing a theory according
to which all living beings, human beings included, evolved from common simple
ancestors. According to the principles of evolutionary theory, usually there are too many
individuals of a given species competing for limited resources. The individuals with
superior characteristics are more likely to win in the competition. This hypothesis,
coupled with the laws of inheritance, according to which children inherit their traits from
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their parents and occasionally mutations occur, lead to the conclusion that the
characteristics more useful in a given environment would gradually prevail.
Darwin’s contemporary Herbert Spencer (1892) speculated on the ethical
implications of evolutionary theory. His thought, known as Social Darwinism,
emphasizes the progressive nature of the evolutionary process and equates this
progressive nature with the moral good. The people who are better adept to certain social
environment would naturally become better off than the rest. According to Spencer, the
state intervention into the life of a society should be minimal. The laissez-faire principle
maximizes the competition, thus mimicking the nature’s way of selecting the fittest
individuals.
Darwin’s ideas had a somewhat different twist in the thought of a German thinker
Ernst Haeckel (1868). For him, the basic unit of evolution is not the Spenserian
individual, but rather the society as a whole. Impressed by Germany’s quick rise to
become a world power, Haeckel glorified the cohesion of its institutions. In the FrancoPrussian war in 1870-71, according to Haeckel, it was Germany which triumphed over
France rather than the Germans triumphing over the French. Haeckel thinks a modern
human being is so absorbed into the social apparatus that his real strength lies in his
functions relative to the apparatus rather than in his own individual abilities taken apart
from the social structure. Therefore, Haeckel argues, the evolutionary process selects the
social systems which are best organized as opposed to the individuals who are best suited
for competition in the laissez-faire environment.
The problems with 19th century Social Darwinism are twofold. First, Social
Darwinism is associated with the infamous eugenics movements in the first half of 20th
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century in the U.S. and Germany. For example, the notion that the failure to adapt to the
current social environment can be entirely blamed on the unsuccessful individual or the
social group permeated the Nazi ideology. The justification which Hitler’s government
provided for sterilizing or putting to death the mentally ill and the mass extermination of
the Jews was that these people were in some relevant sense “weak”. Most importantly,
Hitler portrayed his actions as the ethically right thing to do. Thus, not surprisingly, many
contemporary thinkers do not eagerly glorify the successful, which used to be so
characteristic of Social Darwinism.
In theoretical context, Social Darwinism is accused of the naturalistic fallacy.
Already in the 17th century, David Hume (1978) pointed out that you cannot infer a
normative rule from a description. The way the world ought to be cannot be derived from
the way the world actually is. Yet Social Darwinism attempts to do precisely that by
giving a naturalistic account of ethical values based on the theory of evolution. In the
most famous attack against reductionism in ethics, whether the reduction is done along
Social Darwinist or some other lines, G. E. Moore (1903) argues that the ethical facts, in
much the same way as the physical, are simply facts about the world and therefore ethical
norms are valid only insofar as they reflect them. Any attempt to justify an ethical norm
in terms of physical facts, according to Moore, is doomed since the gulf between the
physical and the ethical is too wide. Moore thinks that there is a kind of sixth sense which
gives us access to the ethical facts just as sight gives us access to color.
Although evolutionary ethics has its roots in Social Darwinism, they differ in
some important respects. The notion of progress plays an important part in Social
Darwinism, while it is not as significant in evolutionary ethics. Social Darwinists, such as
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Spencer and Haeckel, employ the idea of progress to close the gap between the
descriptive ‘is’ and the normative ‘ought’. A typical Spenserian attaches some kind of
moral value to the evolutionary development from simple to complex organisms.
Consequently, human beings possess a higher moral status than, for example, ants.
Spencer (1892) advocates competition which keeps the process going, and this
competition in some sense is the moral law of the universe. The U. S. eugenics movement
in the beginning of the 20th century and Nazism also emphasized the progressive nature
of evolutionary development.
While evolutionary ethicists look at the evolutionary process to explain our
ethical intuitions, some of them are hesitant to regard it as progressive. Michael Ruse
(1995a), one of the most prominent contemporary philosophers of biology, argues that
people discerning progress in evolution usually justify their view by invoking
anthropocentric criteria. According to them, the evolutionary process is progressive since
it produced human beings, and human beings are better than other organisms in many
respects, such as intelligence or the ability to reflect upon their own actions. However, as
Ruse argues, we can just as well set the criteria, such as the ability to survive in a variety
of environments, according to which the AIDS virus is the supreme product of evolution.
Moreover, Ruse observes that human beings, like the dinosaurs, might one day become
extinct, perhaps as a result of an environmental catastrophe, which ironically might be
caused by the industrial activities on behalf of the human beings themselves (Ruse,
1995a).
As for Moore’s (1903) naturalistic fallacy argument, it is unclear whether it
seriously affects the evolutionary explanations of ethics. Moore’s argument depends on
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an implausible account of ethical good as indefinable in naturalistic terms (Moore, 1903).
Such account requires some clarification of how physical human beings can get access to
the non-physical features of the world. Platonism, which assumes that the world can be
divided into physical and non-physical parts, has virtually no adherents among
contemporary philosophers precisely because no adequate account of how the two parts
interact has been proposed yet, nor is it likely to be.
Contrary to Moore’s judgment, an attempt to analyze an elusive concept, such as
the ethical good in naturalistic terms, seems to be an asset and not a shortcoming. Given
the implausibility of a dualistic worldview, which posits the existence of both physical
and non-physical entities, it is unclear what the status of the seemingly non-physical
items, such as the ethical good, should be. There are three options: you could either
accept dualism and ignore its critics, you could deny that there is such thing as the ethical
good, or you could attempt to give an account of the ethical good in physical terms.
Maintaining dualism does not seem to be an intellectually viable option, since the
interaction between the physical and non-physical simply begs the question of how
precisely the interaction occurs. A nihilist view is also unsatisfactory. Most of us do have
certain ethical intuitions, such as that murder is wrong. Since both dualism and nihilism
are implausible, naturalism is the best route to take.
Evolutionary Metaethics
The subject matter of ethics can be divided into substantive ethics and metaethics
(Ruse, 1995a). Substantive ethics discusses questions such as what is the right thing to do
in given circumstances as well as provides explanations for particular ethical judgments.
A typical substantive ethics question asks under what conditions killing is wrong. In
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answering this question, an ethicist is usually expected to give some kind of justification
for his judgment. Metaethics looks at the ethical system as a whole. A metaethicist could
be interested whether there are objective facts about the world corresponding to certain
parts of an ethical system, or what the status of an ethical theory is given there are no
such facts.
Evolutionary philosophers are divided on the central metaethical question about
the sources of morality. Some, including Francisco Ayala (1987), claim that morality is
essentially a cultural phenomenon and should not be viewed as an adaptation under the
pressure of natural selection. According to Ayala, human beings are capable of making
ethical judgments in virtue of their rationality, and rationality sets us apart from other
animals. While Ayala would concede that our ability to reason is a product of evolution,
he would nevertheless disagree that morality could be considered an adaptation on the
grounds that obeying the currently accepted ethical norms in many situations is not
“evolutionary advantageous” (Ayala, 1987, p. 237).
Ayala’s idea that there is a fundamental difference between human beings, who
are full moral agents, and other animals, which are not, is implausible. Numerous
biological studies have demonstrated that some animals, such as chimpanzees, have the
ability to reason, which is in principle similar to that of human beings (Ruse, 1986). If
morality, as Ayala argues, is the product of human rationality, then it is natural to
conclude that chimpanzees also possess some form of morality, although probably less
developed than that of human beings. The counterargument is that chimpanzee’s
rationality is “either genetically determined or elicited by training (“conditioned
responses”)” (Ayala, 1987, p. 241), while for human beings, apparently, there are some
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other factors operating. This counterargument, however, is at odds with the dominant
scientific view that human behavior is the product of the interaction between genes and
environment (Dr. Burk, personal communication, February 2004). Human reasoning,
obviously, is way more complex than that of a chimpanzee, but both operate and develop
under the same principles, namely, their ways of functioning emerge from the genetic
composition of an organism interplaying with the surroundings.
An alternative evolutionary view about metaethics denies the supreme importance
of culture in forming our ethical norms. According to this view, an ethical system is
simply an adaptation (Ruse, 1995a), analogous, for example, to vision or hearing. Just
like vision enhances the ability of an organism to find its own way around the
environment, so the evolutionary advantage of an ethical system consists in the organism
being better suited to function within a social group. While culture certainly does have a
role in forming and especially transmitting ethical norms, on this view, as opposed to
Ayala’s, the ultimate explanation for morality sociobiological.
Game Theory and Ethical Norms
A major concern for the ethics à la Ruse is to explain how altruistic behavior,
which is often prescribed by our ethical norms, can be evolutionary advantageous. It
seems that if I altruistically give you a certain portion of my resources, then I
disadvantage myself in the struggle for survival and, ultimately, reproduction.
Withholding the resources for myself and letting my starving neighbor die would
apparently make more evolutionary sense, since I at once get rid of a competitor and keep
intact all of my wealth, which I might need in the uncertain future.
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In order to demonstrate the advantages of altruism, we can turn to the famous
Prisoner’s Dilemma (Axelrod, 1987). The description of the dilemma is roughly this: two
individuals, A and B, have to make a joint action. Both A and B have two options. They
can either cooperate or defect. In case both of them cooperate, they get a modest payoff.
If A defects and B cooperates, A gets a large payoff, while B suffers a large loss, and vice
versa. If both of them defect, both suffer a modest loss. A and B must make their decision
to cooperate or to defect prior to finding out what the other one of them has decided, and
once made, the decision cannot be changed.
If we think of rationality as a selfish utility maximization, then the rational
decision for both A and B is to defect. Let us consider the options A has. A knows that
his decision is not going to affect that of B, and that B has already chosen his option
before the joint action takes place. Suppose B has chosen to cooperate. Then A’s choice
to cooperate would bring him a modest as opposed to a large benefit which he would get
by defecting. Suppose that B has chosen to defect. Again, A is better off defecting, since
in that case he would suffer only a modest loss. Similar reasoning also leads B to defect.
Thus using rational selfish reasoning, A and B defect, and they suffer a modest loss,
while both of them would have been better off cooperating.
The Prisoner’s Dilemma gets an interesting and important twist if we consider it
played multiple times among a large number of individuals. Instead of having just A and
B, suppose we have a population of A1, A2, …, AN, where N is sufficiently large, maybe
1000 or so. For the sake of simplicity, suppose that at each time period T1, T2, …, TM,
where M is again reasonably large, some randomly selected individuals are paired off to
play the Prisoner’s Dilemma and some skip the turn. At the end of the time sequence, the
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resources of each individual, which he has accumulated playing the game, are calculated
and the winner is declared.
A few decades ago, Robert Axelrod (1980) invited scholars to submit strategies
for an iterated Prisoner’s Dilemma competition. Although numerous intricate strategies
were proposed, Axelrod’s computer simulations suggest that the best strategy to play the
iterated Prisoner’s Dilemma is tit-for-tat (Axelrod, 1987). Tit-for-tat is characterized by
two simple rules: cooperate on the first encounter with player X and repeat the last X’s
decision on subsequent encounters. Suppose A1 adopted tit-for-tat. He would cooperate
with A2 on the first meeting. If A2 defected, A1 would defect on the second meeting.
However, if A2 had a change of heart and chose to cooperate on the second meeting, then
A1 would reciprocate on the third meeting, and so on.
Some studies suggest that certain important features of evolution could be thought
of as an iterated Prisoner’s Dilemma (Dawkins, 1976). Suppose A and B are competing
over scarce resources. If A decides to fight (defect) and B gives in (cooperates), then A
kills B or drives him away and reaps all the benefits. A and B could also peacefully share
the resources, in which case they each get a half, or they could both fight, in which case
both A and B suffer some losses in combat and share the resources in the end. Although
the real world is way more complicated, the Prisoner’s Dilemma captures the idea that
joint cooperation is better than joint defection, although individually the players are
inclined to defect.
It makes sense that during the course of evolution a stable pattern of behavior
among a given population would emerge (Dawkins, 1976). In our model such pattern of
behavior is a game strategy telling a player whether to cooperate or to defect given his
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past game history. Axelrod’s studies (1987) suggest that in most circumstances tit-for-tat
would prevail. In a population made up only of tit-for-tatters we would never see
defection, since a tit-for-tatter never defects first. If there is an occasional hawk, that is, a
selfish player who always defects, he would do well on his first encounters. However,
once a tit-for-tatter meets the hawk for a second time, both of them would defect and
suffer a modest loss. Thus eventually, when most of the population finds out about the
hawk, he would suffer losses on the majority of the encounters, while tit-for-tatters would
successfully accumulate their resources by cooperating among themselves. Depending on
the set up of the game, a tit-for-tatter would probably have more resources than a hawk
(Dawkins, 1976).
Ethical norms prescribing altruistic behavior probably have emerged as useful
rules-of-thumb for cooperation (Ruse, 1995a). As game theoretical models and computer
simulations suggest, a society where social interactions are governed by such rules would
do better than a society without them (Axelrod, 1987). Thus it is reasonable to suppose
that during the course of history the former prevailed over the latter, and that is why
today we have ethical norms. Ethical norms, just as vision, can be viewed as an
adaptation, since it confers an evolutionary advantage upon the populations which adopt
them.
Conclusion
As opposed to the traditional systems of ethics, which most often attempt to
discover the right thing to do in a given situation, evolutionary ethics looks for an
explanation for the ethical intuitions that we possess. Game theoretical models capturing
the important features of evolution give some versions of evolutionary ethics the rigor
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comparable to that of a social science. The intersections between ethics, sociobiology,
psychology, and sociology cannot be ignored in order to give a unified account of the
social world we inhabit.
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References
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