Read Darwin's Dangerous Idea Online
Authors: Daniel C. Dennett
The craftsmanship of this passage is itself remarkable. The repetition of 201-9- For a discussion and survey of this and other interpretations of Nietzsche's nothe orphanage drama year after year seems to rob the little world of any real torious idea of eternal recurrence, see Nehamas 1980, which argues that by "scientific"
meaning. But why? Why exactly should it be the repetition of the fire Nietzsche meant specifically "not-teleological." A recurring—but, so far, not eternally inspector's lament that makes it sound so hollow? Perhaps if we looked recurring—problem with the appreciation of Nietzsche's version of the eternal recur-closely at what that entails we would find the sleight of hand that makes the rence is that, unlike Wheeler, Nietzsche seems to think that
this
life will happen again not because it
and all possible variations on
it will happen over and over, but because there passage "work." Do the little Tyroleans rebuild the orphanage themselves, or is only one possible variation—this one—and it will happen over and over. Nietzsche, in is there a RESET button on this miniature village? What difference would that short, seems to have believed in actualism. I think that this is inessential to an appreci-make? Well, where do the new orphans come from? Do the "dead" ones ation of the moral implications Nietzsche thought he could or should draw from the idea, come back to life (Dennett 1984, pp. 9-10)? Notice that Robbins says that the and perhaps to Nietzsche scholarship as well (but what do I know?).
orphanage
was designed
to catch fire and burn down every Christmas 184 PRIMING DARWIN'S PUMP
Eternal Recurrence
—
Life Without Foundations?
185
Eve. The creator of this miniature world is clearly taunting us, ridiculing the What does need its origin explained is the concrete universe itself, and as seriousness with which we face our life problems. The moral seems clear:
if
Hume's Philo long ago asked: Why not stop at the material world?
It,
we the meaning of this drama must come from on high, from a Creator, it would have seen, does perform a version of the ultimate bootstrapping trick; it be an obscene joke, a trivialization of the strivings of the individuals in that creates itself
ex nihilo,
or at any rate out of something that is well-nigh world. But what if the meaning is somehow the creation of the individuals indistinguishable from nothing at all. Unlike the puzzlingly mysterious, time-themselves, arising anew in each incarnation rather than as a gift from on less self-creation of God, this self-creation is a non-miraculous stunt that has high? This might open up the possibility of meaning that was not threatened left lots of traces. And, being not just concrete but the product of an ex-by repetition.
quisitely particular historical process, it is a creation of utter uniqueness—
This is the defining theme of existentialism in its various species: the only encompassing and dwarfing all the novels and paintings and symphonies of meaning there can be is the meaning you (somehow) create for yourself.
all the artists—occupying a position in the hyperspace of possibilities that How
that
trick might be accomplished has always been something of a differs from all others.
mystery among existentialists, but as we shall soon see, Darwinism does Benedict Spinoza, in the seventeenth century,
identified
God and Nature, have some demystification to offer in its account of the process of meaning-arguing that scientific research was the true path of theology. For this heresy creation. The key, once again, is the abandonment of John Locke's Mind-first he was persecuted. There is a troubling (or, to some, enticing) Janus-faced vision, and its replacement with a vision in which
importance itself,
like quality to Spinoza's heretical vision of
Deus sive Natura
(God, or Nature): in everything else that we treasure, gradually evolves from nothingness.
proposing his scientific simplification, was he personifying Nature or We might pause, before turning to some of these details, to consider where depersonalizing God? Darwin's more generative vision provides the structure our roundabout journey has brought us so far. We began with a somewhat in which we can see the intelligence of Mother Nature (or is it merely childish vision of an anthropomorphic, Handicrafter God, and recognized that apparent intelligence?) as a non-miraculous and non-mysterious—and hence this idea, taken literally, was well on the road to extinction. When we looked all the more wonderful—feature of this self-creating thing.
through Darwin's eyes at the actual processes of design of which we and all the wonders of nature are the products to date, we found that Paley was right to see these effects as the result of a lot of design work, but we found a non-CHAPTER 7:
There must have been a first living thing, but there couldn't have
miraculous account of it: a massively parallel, and hence prodigiously
been one
—
the simplest living thing is too complex, too designed, to spring
wasteful, process of mindless, algorithmic design-trying, in which, however,
into existence by sheer chance. This dilemma is solved not by a skyhook, but
the minimal increments of design have been thriftily husbanded, copied, and
by a long series of Darwinian processes: self-replicating macros, preceded
re-used over billions of years. The wonderful
particularity
or
individuality
of
or accompanied perhaps by self-replicating clay crystals, gradually
the creation was due, not to Shakespearean inventive genius, but to the
advancing from tournaments of luck to tournaments of skill over
a
billion
incessant contributions of chance, a growing sequence of what Crick (1968)
years. And the regularities of physics on which those cranes depend could
has called "frozen accidents."
themselves be the outcome of a blind, uncaring shuffle through Chaos. Thus,
That vision of the creative process still apparently left a role for God as
out of next to nothing, the world we know and love created itself.
Lawgiver, but this gave way in turn to the Newtonian role of Lawfinder, which also evaporated, as we have recently seen, leaving behind no Intel-CHAPTER 8:
The work done by natural selection is R and D, so biology is
ligent Agency in the process at all. What is left is what the process, shuffling
fundamentally akin to engineering, a conclusion that has been deeply re-through eternity, mindlessly finds (when it finds anything): a timeless Pla-sisted out of misplaced fear for what it might imply. In fact, it sheds light on
tonic possibility of order. That is indeed a thing of beauty, as mathematicians
some of our deepest puzzles. Once we adopt the engineering perspective, the
are forever exclaiming, but it is not itself something intelligent but, wonder
central biological concept of
function
and the central philosophical concept
of wonders, something intelligible. Being abstract and outside of time, it is
of
meaning
can be explained and united. Since our own capacity to respond
nothing with an
initiation
or
origin
in need of explanation.
to and create meaning
—
our intelligence
—
is grounded in our status as
advanced products of Darwinian processes, the distinction between real and
artificial intelligence collapses. There are important differ-12. Descartes had raised the question of whether God had created the truths of mathematics. His follower Nicolas Malebranche ( 1638-1715) firmly expressed the view that they needed no inception, being as eternal as anything could be.
186 PRIMING DARWIN'S PUMP
ences, however, between the products of human engineering and the products
of evolution, because of differences in the processes that create them. We are
just now beginning to get the grand processes of evolution into focus, by
directing products of our own technology, computers, onto the outstanding
CHAPTER EIGHT
questions.
Biology Is Engineering
1. THE SCIENCES OF THE ARTIFICIAL
Since World War II the discoveries that have changed the world were
not made so much in lofty halls of theoretical physics as in the less-noticed labs of engineering and experimental physics. The roles of pure
and applied science have been reversed; they are no longer what they
were in the golden age of physics, in the age of Einstein, Schrö-dinger,
Fermi and Dirac.... Historians of science have seen fit to ignore the
history of the great discoveries in applied physics, engineering and
computer science, where real scientific progress is nowadays to be
found. Computer science in particular has changed and continues to
change the face of the world more thoroughly and more drastically than
did any of the great discoveries in theoretical physics.
—NICHOLAS METROPOLIS 1992
In this chapter I want to trace some of the overlooked and underappreciated implications of a central—I venture to say the central—feature of the Darwinian Revolution the marriage, after Darwin, of biology and engineering. My goal in this chapter is to tell the positive side of the story of biology as engineering. Later chapters will deal with various assaults and challenges, but before they steal the limelight, I want to make out the case that the engineering perspective on biology is not merely occasionally useful, not merely a valuable option, but the obligatory organizer of all Darwinian thinking, and the primary source of its power. I expect a fair amount of emotional resistance to this claim. Be honest: doesn't this chapter's title provoke a negative reaction in you, along the lines of "Oh no, what a dreary, Philistine, reductionist claim! Biology is
much
more than engineering!"?
The idea that a study of living forms is at least a close kin to engineering has been available since Aristotle's own pioneering investigations of organ-188 BIOLOGY IS ENGINEERING
The Sciences of the Artificial
189
isms, and his analysis of teleology, the fourth of his causes, but only since reflexive extension of his idea to itself: the evolution of the Darwinian Darwin has the idea begun to come into focus. It is quite explicit, of course, memes about evolution has been not just accompanied, but positively sped in the Argument from Design, which invites the observer to marvel at the along, by competition between ideas. And as he hypothesized with regard to cunning interplay of parts, the elegant planning and exquisite workmanship organisms, "competition will generally be most severe between those forms of the Artificer. But engineering has always had second-class status in the which are most nearly related to each other"
(Origin,
p. 121). Biologists intellectual world. From Leonardo da Vinci to Charles Babbage to Thomas themselves have not been immune to the heritage of negative attitudes Edison, the engineering genius has always been acclaimed but nevertheless towards engineering, of course. What is the hankering after skyhooks, after regarded with a certain measure of condescension by the mandarin elite of all, but the fond hope that a miracle will somehow come along to lift us science and the arts. Aristotle did not help matters by proposing a distinction, above the cranes? Continued subliminal resistance to this feature of Darwin's adopted by the medievals, between what was
secundum naturam,
according fundamental idea has heightened controversy, impeded comprehension, and
to
nature, and what was
contra naturam,
against nature, artificial.
distorted expression—while at the same time propelling some of the most Mechanisms—but not organisms—were
contra naturam.
Then there were important challenges to Darwinism.
the things that were
praeter naturam,
or wnnatural (monsters and mutants), In response to these challenges, Darwin's idea has grown stronger. Today and die things that were
super naturam
—miracles (Gabbey 1993). How we can see that not only Aristotle's divisions but also other cherished com-could the study of what was
against
nature shed much light on the glories—
partmentalizations of science are threatened by its territorial expansion. The yea, even the monsters and miracles—of nature?
Germans divide learning into
Naturwissenschaften,
the natural sciences, and The fossil traces of this negative attitude are everywhere in our culture.
Geistesiwissenschaften,
the sciences of mind, meaning, and culture, but this For instance, in my own home discipline of philosophy, the subdiscipline sharp divide—cousin to C. P. Snow's Two Cultures (1963)—is threatened by known as philosophy of science has a long and respected history; many of the prospect that an engineering perspective will spread from biology up the most eminent and influential philosophers these days are philosophers of through the human sciences and arts. If there is just one Design Space, after science. There are excellent philosophers of physics, philosophers of biology, all, in which the offspring of both our bodies and our minds are united under philosophers of mathematics, and even of social science. I have never even one commodious set of R-and-D processes, then these traditional walls may heard anybody in the field described as a philosopher of engineering—as if tumble.
there couldn't possibly be enough conceptual material of interest in Before proceeding, I want to confront a suspicion. Since I have just engineering for a philosopher to specialize in. But this is changing, as more granted that Darwin himself didn't appreciate many of the issues that have to and more philosophers come to recognize that engineering harbors some of be dealt with if the theory of evolution by natural selection is to survive, isn't the deepest, most beautiful, most important thinking ever done. (The title of there something trivial or tautological about my claim that Darwin's idea this section is taken from Herbert Simon's seminal book [1969] on these survives all these challenges? No wonder it can keep on spreading, since it topics.)