The philosopher Daniel C. Dennett's new book shows world-encompassing ambition. He writes with clarity and ease on neuroscience, chemistry, computer science, linguistics, philosophy, biology, and much more - all to address two questions: "How come there are minds? And how is it possible for minds to ask and answer this question?"
Bacteria and J.S. Bach represent extreme poles on a spectrum that runs from the mindless, bottom-up design work of natural selection to the highly intentional, top-down designs crafted by a brilliant human mind. But the latter exists only because of the former - minds emerged from the mindless, and comprehension from the uncomprehending. "A process with no Intelligent Designer can create intelligent designers who can then design things that permit us to understand how a process with no Intelligent Designer can create intelligent designers who can then design things," he writes in a sentence that rewards rereading.
Dennett loves to organize his ideas with alliterative slogans: design without designers, competence without comprehension, and reasons without reasoners are among his favorites. One central idea he defends throughout the book is that cultural "memes," like genes, are in a perpetual Darwinian competition to reproduce. Memes reproduce culturally, not genetically, spreading copies of themselves in the minds of their hosts, and they evolve and spread much more quickly than the products of genetic evolution.
Maybe Dennett, with his catchy alliterative phrases, is just trying to promote the survival of his own mental offspring. He gets far-fetched with this idea, suggesting words may be parasitically occupying human brains to further their own reproductive goals. This is one of several deployments of intentional language that do more to confuse than clarify the subject of cultural evolution.
The book has other flubs. Dennett gets the etymology of the word ontology wrong, and he slights the achievements of female geniuses in the arts and sciences. (He musters a handful, then claims there are no others.)
But the work as a whole is a delightful summation of Dennett's distinguished career pondering some of the hardest questions in science. We're reminded that philosophers, when they venture beyond the cloistered boundaries of scholarly disputes, can still make important contributions to some of the fundamental questions that motivated the birth of their discipline in the first place.
This review originally appeared in the Washington Post.