EvoluTIonARy BIology 21
Ethics, religion, and evolution
In the world of science, the reality of evolution has not been in doubt for more than
100 years, but evolution remains an exceedingly controversial subject in the United
States and a few other countries. The creationist movement opposes the teaching of
evolution in public schools, or at least demands “equal time” for creationist beliefs.
Such opposition arises from the fear that evolutionary science denies the existence of
God, and consequently, that it denies any basis for rules of moral or ethical conduct.
Science, including evolutionary biology, is silent on the existence of a super-
natural being or a human soul, because these hypotheses cannot be tested. Many
people, including some priests, ministers, rabbis, and evolutionary biologists,
hold both religious beliefs and belief in evolution (see Chapter 22). But to explain
phenomena in the natural world, science must assume that only natural causes
operate, just as most people do in everyday affairs: we assume that there is a
material cause when our car or computer or heart malfunctions. Supernatural
explanations for observable phenomena often do conflict with naturalistic, scien-
tific explanation. A literal reading of some passages in the Bible is incompatible
with the principles of physics, geology, and other natural sciences. Our knowl-
edge of the history and mechanisms of evolution is certainly incompatible with
a literal reading of the creation stories in the Bible’s Book of Genesis—just as it is
incompatible with hundreds of other creation myths people have devised.
Wherever ethical and moral principles are to be found, it is probably not in
science, and surely not in evolutionary biology. Opponents of evolution have
charged that evolution by natural selection justifies the principle that “might
makes right.” But evolutionary theory cannot provide any such precept for
behavior. Like any other science, evolutionary biology describes how the world is,
not how it should be. The supposition that what is “natural” is “good” is called by
philosophers the naturalistic fallacy.
Various animals have evolved behaviors that we give names such as coop-
eration, monogamy, competition, infanticide, and the like. Whether or not these
behaviors ought to be—and whether or not they are—moral, is not a scientific
question. The natural world is amoral—the concepts of “moral” and “immoral”
simply do not apply outside the realm of human behavior. Despite this, the
concepts of natural selection and evolutionary progress were taken as a “law
of nature” by which Marx justified class struggle, by which the Social Darwin-
ists of the late eighteenth and early nineteenth centuries justified economic
competition and imperialism, and by which the biologist Julian Huxley justi-
fied humanitarianism [11, 21]. Most philosophers consider all these ideas to be
indefensible instances of the naturalistic fallacy. Infanticide by lions and langur
monkeys does not justify infanticide in humans; monogamy in penguins does
not imply that humans should do the same. Evolution provides no basis for
human ethics.
Go to the
Evolution Companion Website
EvoluTIon 4 E.SInAuER.CoM
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