BOOK REVIEW
Defending Darwinism
Richard Bellon
Darwinism and Its Discontents. Michael Ruse. x + 316 pp.
Cambridge University Press, 2006. $30.
The historian and philosopher Michael Ruse has spent decades
explaining the nature of the Darwinian Revolution. The result has
been a constant stream of innovative, provocative, informative,
witty and entertaining scholarship. No other contemporary writer has
Ruse's knack for seamlessly weaving together history, philosophy,
theology and science.
In his latest salvo, Darwinism and Its Discontents, Ruse
turns his good-natured pugnacity to a robust and comprehensive
defense of the theory of evolution by natural selection as
elaborated by Charles Darwin in On the Origin of Species
(1859). Ruse's emphasis on Darwinism—which he defines as
"natural selection as the chief causal process behind all
organisms"—widens the book's scope beyond a conventional
critique of creationism. He confronts the full range of people who
treat Darwin's theory with suspicion, squeamishness or malign
neglect. This includes secular thinkers who would indignantly reject
the creationist label but nonetheless, in Ruse's view, "stand
virtually back to back with the religious critics" when it
comes to natural selection. He also seeks "to defend Darwinism
from false (or misguided) friends," those who bastardize or
misapply Darwin's ideas to advance their own cultural agendas. This
is a book for anyone interested in what Darwinism can tell
us—and more important, what it cannot tell us—about such
profound and profoundly divisive issues as the literal
interpretation of the Bible, the reality of free will, the existence
of purpose and direction in the universe, the origin of life, the
foundations of human ethical behavior, and the moral and political
implications of human differences.
Ruse argues that the unrelenting controversies that cling to
evolution reflect its 18th-century origins. Enlightenment thinkers,
including Darwin's own grandfather, sought a non-Christian
alternative history of creation. Evolution, by wrapping the craving
for social and cultural advancement in a narrative of biological
progress, fit the bill nicely. Any answers to unresolved scientific
questions provided by pre-Origin evolutionary theory were,
in Ruse's view, only happy accidents. In that era, conservative
Christians were not being paranoid when they interpreted evolution
as a dagger pointed directly at their spiritual and cultural authority.
Ruse believes that only with Origin did evolution debut as
a fully legitimate scientific theory, one designed primarily to
provide rational explanations for the regularities of the physical
world, rather than one concerned chiefly with the validation of
underlying metaphysical commitments. Darwin had neither the stomach
nor the motivation to join fights over worldview, but as he
understood acutely, he could never entirely extricate his theory
from these battles, as much as he might have wished to do so.
Ironically, the more successfully he and his colleagues demonstrated
the scientific validity of evolution, the more potent the theory
became for extrascientific purposes.
From the moment that Origin became a surprise instant
bestseller, Darwin lost direct control over ideas to which his name
was (often dubiously) affixed. Although no scientifically literate
person rejected evolution by the time of Darwin's death in 1882,
acceptance of natural selection as the chief mechanism in evolution
remained a minority view among biologists. Natural selection had
legitimate scientific problems, suffering most significantly from
the lack of any adequate theory of heredity. Nonetheless Ruse
believes that the unwillingness, even (or perhaps especially) among
many biologists, to employ evolution as straight science stunted its
development as a mature causal theory with natural selection at its
heart. Natural selection was scientifically resurrected only in the
1930s with the rise of population genetics. Historians argue over
aspects of Ruse's interpretation of this history. But he is
certainly correct to insist that evolutionists of the 19th century
and early 20th century bear much of the blame for the ideological
baggage that has complicated Darwinism's place in both science and culture.
One complication is that, for many religious conservatives,
evolution in any guise retains the indelible stench of blasphemy,
for which creationism is the only fumigant. Most notoriously, some
Christians reject evolution on the conviction that Genesis contains
a direct and irrefutable eyewitness account of creation. Others have
launched a more sophisticated attack on evolution under the guise of
intelligent design. That assault is grounded more in a visceral
dislike of natural selection's status as a blind, undirected (and
value-free) mechanical process than in a commitment to biblical
literalism. Natural selection cannot be true, intelligent-design
theorists insist, because it is impossible for any blind process to
produce integrative adaptive functioning; the only legitimate
explanation for the so-called "irreducible complexity" of
life is the direct conscious activity of a designing intelligence.
Ruse takes a multipronged approach to these various creationist
attacks. First, he fights theology with theology by drawing on a
rich nonliteralist tradition stretching back to Saint Augustine in
the fifth century. Second, Ruse gleefully demolishes one specific
creationist scientific claim after another. He uses the Krebs cycle,
for example, to illustrate concisely and convincingly that
"irreducibly complex" systems are in fact not
"irreducible" at all, except to those suffering under
"great ignorance of the way in which Darwinian evolution works."
Ruse's most effective strategy against creationism involves a robust
general defense of the scientific method. The criteria for good
science do not rest on ideological sleight of hand or arbitrary
philosophical preferences (as, in a revealing confluence of
agreement, both creationists and certain leftist postmodernists
would have us believe) but on proven success in acquiring and
organizing knowledge of the natural world. Ruse cheerfully
acknowledges that no irrefutable logical reason exists for excluding
any fantastical proposed cause relating to the physical operation of
the universe. God very well might have directly engineered the
bacterial flagellum or created rocks with fossils embedded in them
already, but, as far as that goes, John F. Kennedy might have been
"a transvestite for whom a substitute was killed in
Dallas." But in science, we should categorically reject
explanations that are not bound by laws—not because they are
necessarily wrong (although available experience strongly suggests
that they probably are) but because they are sterile. Science would
have long ago ground to an ignominious halt if supernatural causes
had become an acceptable part of scientists' explanatory tool kit.
All the great scientific discoveries of the past half millennium
have only been made because stubborn individuals refused to throw up
their hands in the face of seemingly intractable puzzles. In the
case of contemporary mysteries—Ruse uses the origin of life as
a particularly effective example—it would be not only wrong
but irrational to break the methodological embargo on supernatural
explanations, given its centuries of success.
Creationist alternatives to Darwinism collapse for nonmethodological
reasons as well. Ruse draws heavily on "consilience"
(literally, "jumping together"), an idea elaborated by
William Whewell, Darwin's favorite philosopher of science. Ruse,
following Darwin, agrees with Whewell that the best test of a theory
is its ability to unify disparate information within a coherent
explanatory framework. Most theories can more or less plausibly
account for any single class of evidence. In pure isolation,an
evolutionary explanation of the fossil record is not absolutely
superior to a creationist one—a situation that, as Ruse notes
ruefully, wily creationists like Duane Gish exploit to devious
effect. But evolutionary paleontology "jumps together"
beautifully with evolutionary explanations of biogeography,
morphology, genetics and the like; creationist paleontology
wretchedly flies apart from creationist accounts of such collateral
phenomena. Evolution, and evolution alone, succeeds in binding
together the dizzyingly complex phenomena of life within a common
theoretical structure while simultaneously providing scientists with
the conceptual tools to expand the boundaries of empirical
knowledge. Allow miraculous explanations into science, and
creationism's abject failure to offer any adequate consilience would
still mark it as an intellectual dead end.
The secular skeptics of natural selection form a more heterogeneous
group, and, perhaps inevitably, Ruse's engagement with them lacks
the momentum that drives his discussion of creationism. In many
cases, as Ruse concedes, critics are responding, understandably if
unfortunately, not to Darwin's core ideas but to the ideological
uses to which evolution has been put: "Some dreadful stuff has
been fobbed off under the umbrella of evolution, and even when it is
not that dreadful, some very shaky assumptions have been
incorporated." His strategy relies on demonstrating that
Darwinism, properly understood, does not really stand behind any of
the often-noxious philosophies that have claimed its authority.
Despite well-documented abuses, Ruse argues persuasively that
"there is no good reason to think that . . . the professional
side of modern Darwinism . . . is simply an excuse for promulgating
the values of modern (or past) society."
Ruse's defense of natural selection against critics within
evolutionary biology is sure-handed but is neither as decisive nor
as satisfying as the rest of the book. The introduction laments that
"well-qualified and articulate evolutionary biologists . . .
have been showing so visceral a hatred of Darwinian thinking that
one suspects that their objections cannot be grounded purely in
theory or evidence." Ruse hints darkly that Marxism may be at
the root of most of it. This assertion is overblown and unfair. The
late Stephen Jay Gould, one of Ruse's main targets, took great pains
to insist that he wanted to restructure and extend Darwin's vision,
not replace it. Ruse provides little reason not to take Gould at his
word or to conclude more generally that like-minded biologists are
any less committed to a rational explanation of the living world
than their more selection-minded colleagues.
Fortunately, Ruse does not expand on this inflammatory line of
argument. (It is there, no doubt, more to tweak the noses of
friendly adversaries than to launch a blistering assault on enemies,
but any wink of his eye will probably be lost on readers unfamiliar
with his long career as a polemicist.) In the heart of the book he
does acknowledge that biologists such as Gould and Richard Lewontin
raise legitimate issues about the limits and restrictions on natural
selection. Concessions made, Ruse then draws dexterously on
scientific evidence and evolutionary logic to argue that the points
made against robust selectionist thought are not nearly as telling
as the critics like to think, and so no good reason exists for a
significant refurbishment of current orthodoxy.
No reader, no matter what his or her sympathies, will finish
Darwinism and Its Discontents without finding
something, and perhaps much, to dispute—and Ruse clearly
enjoys a good debate too much to want anyone to nod in dull assent
to all of his points. In his determination to vanquish all critics
of uncontaminated Darwinian thought, he does not distinguish as
clearly as he should between his opponents. His targets (take Gould
and Gish on the extremes) are all "anti-Darwinians" only
in the same way that oak trees and chimpanzees are nonmembers of the
genus Homo. Although Ruse's targets are a ragtag bunch, the
core logic he uses to defend Darwinism contains a powerful and
compelling coherence. We see that evolution works worst when
elevated to the status of a secular religion or otherwise
subordinated to the service of extrascientific commitments.
"Beware of anything that answers everything," Ruse
cautions. "It usually ends by answering nothing. And that is
certainly not true of Darwinism." We see that evolution works
best when deployed to address tightly defined questions about the
living world. For Ruse, pragmatic to his bones, this is the ultimate point:
Darwinian biology . . . does what is needed to tell us in a
disinterested fashion about the world of experience. It works, and
that in the end is why it deserves our attention and support. Until
and unless a more powerful rival appears on the scene, that is why
we should be Darwinians.
And to that, in light of the mischief that results when evolution is
subordinated to metaphysical ends, we are forbidden to say
"Amen."