Dennett: Darwin's Dangerous Idea

From Scienticity

Scienticity:
Readability:
Hermeneutics:
Charisma:
Recommendation:
Ratings are described on the Book-note ratings page.

Daniel C. Dennett, Darwin's Dangerous Idea : Evolution and the Meanings of Life. New York : Simon and Schuster, 1995. 586 pages.

I read Dennett's book immediately after reading Richard Dawkins' The Blind Watchmaker. Both books are strong arguments supporting Darwinism; together they make a powerful effect. The two had such similar goals that some of the following discussion about both is shared between the two book notes.

These two books attack what started out -- and still remains -- the biggest conceptual hurdle for most to overcome in accepting natural selection as the mechanism of evolution ("Darwin's Dangerous Idea", as Dennett names it): How could all the complexity of the natural world, its apparent design, have arisen naturally through the seemingly random process of evolution? Both authors build very strong arguments along very similar lines, but they do it with distinctly individual voices and styles.

Dawkin's style is excited exuberance as he hurries breathlessly from topic to topic: too little time, too many fascinating things to talk about to dwell for long on one. There is no feeling of being intellectually short changed, though, more a feeling of going for the big picture and an intuitive understanding. In contrast Dennett takes a slower, more philosophically considered approach: this topic is too interesting and too complex to speed ahead – let's linger and really, really understand it. By the end, the big picture emerges from layers of careful consideration. Each suits its author, the two products are stimulating, and both succeed admirably. My own taste inclines more towards Dennett's approach, but I found both books engaging and enlightening.

Given the similarities of thesis, it's certainly not surprising that both books hike along similar paths, albeit in different ways. Mark it down, perhaps, as convergent evolution that both authors felt the need to develop extended metaphors – a chapter in each book – to elucidate the idea that phenotypic expression of the genotype is highly constrained, i.e., very few mutations in the DNA lead to viable creatures, and very few of all imaginable variants in phenotype can likewise be brought about by variations in the genotype. Dawkins invents a computer model to examine the possible mutations in the "genes" of what he calls "biomorphs". Dennett constructs an intellectual model that he calls the "Library of Mendel", patterned after the literary "Library of Babel" of Jorge Luis Borges. Of the two I thought that Dennett's metaphor had more depth to it, but Dawkins' served its purpose well enough.

Despite how thoroughly and digestibly both books present a comprehensive understanding of how natural selection can produce the amazing complexity of plant and animal life on Earth, one has the sinking feeling that those who might profit most from reading these works will probably never actually peek between the covers. On the other hand, even if they are preaching to the choir, it is no doubt beneficial if the choir can sing better than ever after the sermon. In the end – and one can judge this to some extent since both books are now over ten years old – some of the arguments and some of the rhetoric will seep into popular discourse as Darwinism continues on its rocky road to popular acceptance.

I have one odd criticism common to both books: neither satisfactorily answered the question implied by each author's subtitle. I never felt that Dennett gave a satisfactory answer to "what is the meaning of life?", a question apparently at the root of objections for many deniers of evolution by natural selection, a feeling that it leaves life without a reasons, a "meaning". Likewise with Dawkins, I never felt that he demonstrated that the "evidence of evolution" revealed a universe without design, although it's entirely consistent with that; rather that he showed how apparent design could grow through natural selection. But, in the end, these are small criticisms that don't limit or undermine the strength of the argument in either book.

As I reached the end of Dennett's book I was amused by the notion that, in one way, it could be seen as a careful laying out and naming of a whole pile of concepts that Dennett used to construct his understanding of "Darwin's dangerous idea". The notion came to mind when I was reading the last chapter, which was a very satisfactory and streamlined conclusion to the book, and realized that most of the chapter would seem incomprehensible without having read the previous material. The corollary of course, since I think Dennett did an excellent job, is that the final chapter was outstanding in its clarity and economy.

Reading this volume certainly takes an investment of time, but I think the payoff is well worth it.

Choosing excerpts is daunting because there is so much good material. Here are two. The first and shorter comes from a footnote late in the book:

It is worth bearing in mind that mathematics and physics are the same throughout the entire universe, discoverable in principle by aliens (if such there be) no matter what their social class, political predilections, gender (if they have genders!), or peccadilloes. I mention this to ward off the recent nonsense you may have heard emanating from some schools of thought--I speak loosely--in the sociology of science. It is dismaying to read such a wise thinker as John Patrick Diggins falling under its spell:

But, as Mr. Marsden notes, in the past it was assumed that science would be the arbitrator of such disputes, whereas today science is dismissed as simply another way of describing the world verbally rather than knowing it philosophically. In the recent past, religion has been driven from the campus because it lacked scientific credentials. But since that criterion has itself lost its own credentials, Mr. Marsden wonders why religion cannot reclaim its place on the campus. He is right to raise such questions. [Diggins 1994]

It is not "scientism" to concede the objectivity and precision of good science, any more than it is history worship to concede that Napoleon did once rule in France and the Holocaust actually happened. Those who fear the facts will forever try to discredit the fact-finders. [pp. 494--495]

This longer excerpt comes from the first chapter where Dennett is laying out his program.

The Darwinian Revolution is both a scientific and a philosophical revolution, and neither revolution could have occurred without the other. As we shall see, it was the philosophical prejudices of the scientists, more than their lack of scientific evidence, that prevented them from seeing how the theory could actually work, but those philosophical prejudices that had to be overthrown were too deeply entrenched to be dislodged by mere philosophical brilliance. It took an irresistible parade of hard-won scientific facts to force thinkers to take seriously the weird new outlook that Darwin proposed. Those who are still ill-acquainted with that beautiful procession can be forgiven their continued allegiance to the pre-Darwinian ideas. And the battle is not yet over; even among the scientists, there are pockets of resistance.

Let me lay my cards on the table. If I were to give an award for the single best idea anyone has ever had, I'd give it to Darwin, ahead of Newton and Einstein and everyone else. In a single stroke, the idea of evolution by natural selection unifies the realm of life, meaning, and purpose with the realm of space and time, cause and effect, mechanism and physical law. But it is not just a wonderful scientific idea. It is a dangerous idea. My admiration for Darwin's magnificent idea is unbounded, but I, too, cherish many of the ideas and ideals that it seems to challenge, and want to protect them. For instance, I want to protect the campfire song ["Tell Me Why", mentioned in an earlier anecdote], and what is beautiful and true in it, for my little grandson and his friends, and for their children when they grow up. There are many more magnificent ideas that are also jeopardized, it seems, by Darwin's idea, and the, too, may need protection. The only good way to do this--the only way that has a chance in the long run--is to cut through the smokescreens and look at the ideas as unflinchingly, as dispassionately, as possible.

On this occasion, we are not going to settle for "There, there, it will all come out all right." Our examination will take a certain amount of nerve. Feelings may get hurt. Writers on evolution usually steer clear of this apparent clash between science and religion. Fools rush in, Alexander Pope said, where angels fear to tread. Do you want to follow me? Don't you really want to know what survives this confrontation? What if it turns out that the sweet vision--or a better one--survives intact, strengthened and deepened by the encounter? Wouldn't it be a shame to forgo the opportunity for a strengthened, renewed creed, settling instead for a fragile, sickbed faith that you mistakenly supposed must not be disturbed?

There is no future in a sacred myth. Why not? Because of our curiosity. Because, as the song reminds us, we want to know why. We may have outgrown the song's answer, but we will never outgrow the question. Whatever we hold previous, we cannot protect if from our curiosity, because being who we are, one of the things we deem precious is the truth. Our love of truth is surely a central element in the meaning we find in our lives. In any case, the idea that we might preserve meaning by kidding ourselves is a more pessimistic, more nihilistic idea than I for one can stomach. If that were the best that could be done, I would conclude that nothing mattered after all.

This book, then, is for those who agree that the only meaning of life worth caring about is one that can withstand our best efforts to examine it. Others are advised to close the book now and tiptoe away. [pp. 21--22]

-- Notes by JNS