design is an empirical
matter not to be settled by a book on philosophy. The assertion, in any case,
enjoys wide assent (both in Paley's time and our own). Fish gotta swim and birds
gotta fly--and they perform these tasks very well indeed. Let us then focus
on the validity of the inference. Paley can imagine only two alternatives to his
proposition that good and purposeful design implies a designer. A major part of
his book centers on the dismissal of these competing explanations.1. Good
design exists but does not imply creation for its current purpose. Paley saw God
in the correlation of form with function--specifically, in the divine construction
of anatomy for its appointed role: the leg to walk, the hand to write, the mind
to glorify God. But suppose that form comes first and function follows. Suppose
that form arises for other reasons (direct production by physical laws, for example),
and then finds a use based on fortuitous fit. Paley grants that such an alternative
is conceivable. This turn is sometimes attempted to be Given,
viz. that the parts were not intended for the use, but that the use arose out
of the parts. This distinction is intelligible. A cabinetmaker rubs his mahogany
with fish-skin [I didn't know that the skin of dogfish sharks once served as sandpaper];
yet it would be too much to assert that the skin of the dogfish was made rough
and granulated on purpose for the polishing of wood, and the use of cabinetmakers.
This argument may work, Paley allows, for simple structures like the skin
of a dogfish, but surely not for highly complex contrivances, made of hundreds
of parts, all pointing to the same end and each dependent upon all the others.
Nothing so intricate could be made for, one purpose and then fortuitously suited
for something quite different and entirely unanticipated. Paley writes of the
eye: Is it possible to believe that the eye was formed without
any regard to vision; that it was the animal itself which found out, that, though
formed with no such intention, it would serve to see with? 2.
Good design exists and implies production for its current purpose; but adaptations
are built naturally, by slow evolution toward desired ends, not by immediate,
divine flat. Evolutionary alternatives were well understood in Paley's time. Darwin
provided volumes of evidence and discovered a new and plausible mechanism, but
he scarcely invented the concept. Paley could only conceive of
evolution as a purposeful sequence of positive steps, building adaptation bit
by bit. Thus, he attempted to refute a "Lamarckian" theory of natural
change by use and disuse, with inheritance of acquired characters. (I doubt that
Paley, writing in 1802, knew Lamarck's work directly, since his French colleague
had just begun to publish evolutionary views. But use and disuse represented a
common conviction among evolutionists of the time, not an invention made by Lamarck.)
Paley provided both empirical and theoretical refutations. He began factually,
with an old classic--a good example to be sure, but restricted by modesty
to presentation in Latin, lest the unrefined derive some salacious pleasure. Centuries
of disuse do not cause organs to disappear, or even to diminish:
The mammae of the male have not vanished by inusitation; nec curtorum,
per multa saecula, Judaeorum propagini deest praeputium [nor has the foreskin
of Jews become any shorter in offspring through many centuries of circumcision].
(I am reminded of a story told by my father-in-law about life in Saint Louis
just before World War I. Underground copies of Krafft-Ebing's Psychopathia
Sexualis were always in circulation through boys' networks, but all editions
then in print retained the author's original device of printing all the case studies--and
some are doozies, even by today's more permissive standards--in Latin. This
fact, he assured me, provided the only impetus for attentive study of a subject
then universally taught but otherwise roundly despised.) Paley
also provided some powerful theoretical arguments against evolution by Use. If
the elephant's short neck implies a great advantage for a long nose, all well
and good. But what can a poor proto-elephant do with one-tenth of a trunk.
If it be suggested, that this proboscis may have been produced in the long
course of generations, by the constant endeavor of the elephant to thrust out
his nose (which is the general hypothesis by which it has lately been attempted
to account for the forms of animated nature), I would ask, how was the animal
to subsist in the meantime; during the process; until this elongation of snout
were completed? What was to become of the individual, whilst the species was perfecting?
I accept Paley's arguments and might even be tempted to entertain his conclusions
if he had truly accomplished his proper goal of refuting all logically possible
alternatives. I believe that he did consider and dismiss all the potential refutations
that he could conceive. But now we come to the crux of this essay. True originality
is almost always an addition to the realm of the previously conceivable, not a
mere permutation of possibilities already in hand. The prime fascination in studying
the history of science lies in the power of truly novel formulations. Progress
in knowledge is not a tower to heaven built of bricks from the bottom up, but
a product of impasse and breakthrough, yielding a bizarre and circuitous structure:
that ultimately rises nonetheless. Paley missed a third alternative,
but we can scarcely blame him. The alternative is weird and crazy, laughable really.
No sane person would build anything by such a cruel and indirect route. This third
alternative can only work if you have lots of time to spare, and if you are not
wedded to the idea that nature must be both efficient and benevolent. The third
alternative, like the second, identified natural evolution as the source of good
design--thereby sinking Paley's central conviction that adaptation must imply
creation by divine flat. But instead of viewing evolution as purposeful and positive
movement toward the desired goal, this third alternative builds adaptation negatively--by
eliminating all creatures that do not vary fortuitously in a favored direction
and preserving but a tiny fraction to pass their lucky legacy into future generations.
As I said, this third alternative is grossly inefficient and defies the logic
of a clockwork universe, built by our standards and reasoning. No wonder it never
entered Paley's head. The only thing going for this third view--the only reason
for even raising such an unpleasant topic here--is that nature seems to work
this way after all. Nobody ever called this method elegant, but the job gets done.
We call this third view natural selection by survival of the fittest, or Darwinism.
Darwin himself commented most forcefully upon the inefficient and basically unpleasant
character of his process, writing to his friend Joseph Hooker in 1856: "What
a book a devil's chaplain might write on the clumsy, wasteful, blundering, low,
and horribly cruel works of nature!" The key to understanding
Darwin's third alternative lies with a word, unfortunately almost extinct in English,
that- deserves a revival--hecatomb. A hecatomb is, literally, a massive sacrifice
involving the slaughter of 100 oxen--a reference to ancient Greek and Roman
practices. By extension, a hecatomb is any large slaughter perpetrated for a consequent
benefit. Natural selection is a long sequence of hecatombs. Individuals vary in
no preferred direction about an average form for the population. Natural selection
favors a small portion of this spectrum. Lucky individuals in this spectrum leave
more surviving offspring; the others die without (or12
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