Deutsch is interested in neo-­Darwinian accounts of the evolution of culture. Such accounts treat cultural items — languages, religions, values, ideas, traditions — in much the way that Darwinian theories of biological evolution treat genes. They are called “memes,” and are treated as evolving, just as genes do, by mutation and selection, with the most successful memes being those that are the most faithfully replicated. Deutsch writes with enormous clarity and insight about how the mechanisms of mutation and transmission and selection of memes are going to have to differ, in all sorts of ways, from those of genes.

He also provides an elegant analysis of two particular strategies for meme-­replication, one he calls “rational” and the other he calls “anti-rational.” Rational memes — the sort that Deutsch imagines will replicate themselves well in post-Enlightenment societies — are simply good ideas: the kind that will survive rigorous scientific scrutiny, the kind that will somehow make life easier or safer or more rewarding because they tell us something useful about how the world actually works. Irrational memes — which are more interesting, and more diabolical, and which Deutsch thinks of as summing up the essential character of pre-­Enlightenment societies — reproduce themselves by disabling the capacities of their hosts (by means of fear, or an anxiety to conform, or the appearance of naturalness and inevitability, or in any number of other ways) to evaluate or invent new ideas. And one particular subcategory of memes — about which Deutsch has very clever things to say — succeeds precisely by pretending not to tell the truth. So, for example: “Children who asked why they were required to enact onerous behaviors that did not seem functional would be told ‘because I say so,’ and in due course they would give their children the same reply to the same question, never realizing that they were giving the full explanation. (This is a curious type of meme whose explicit content is true even though its holders do not believe it.)”

Another chapter is devoted entirely to the evolution of creativity. At first glance, the ability to come up with new and better ways of doing things would appear to confer an obvious survival advantage. But if that’s how it worked — or so Deutsch argues — then the archaeological record ought to contain evidence of the accumulation of such better ways of doing things that are contemporaneous with the time when the human brain was actually in the process of evolving. And it doesn’t, which would seem to amount to a puzzle. Deutsch has a cute proposal for solving it. The thought is that the business of merely passing on complicated memes, without any thought of innovation, requires considerable creativity on the part of their recipients. Learning a language, for instance, is a matter of inferring, from a small number of examples, a collection of general rules, each with a potentially infinite number of applications, governing the uses of the words involved. In Deutsch’s view, the work of keeping such complex memes in place, from generation to generation, is no less a creative business than the work of improving them.

This, as I said, is cute, and typical of the dexterity of Deutsch’s mind, but it’s hard to know how seriously to take it. Wouldn’t it be a reproductive advantage to have a heritable capacity to think on your feet, and outside the box, in a sticky situation, whether or not any particular thought you have ends up getting preserved, and passed down to your children, and enshrined in the practice of a whole society? And isn’t it possible that creativity was never selected for at all, but arose as a byproduct of the selection of something else? As to the business of learning a language — well, gosh, haven’t linguists been thinking about these sorts of questions very hard, and very systematically, and along very different lines, for decades now? If Deutsch has reasons for thinking that all of that is somehow on the wrong track, he ought to tell us what those reasons are. As it is, none of that gets so much as a mention in his book.

And there are, in some places, explicit and outrageous falsehoods. Deutsch insists again and again, for example, that the only explanation we have for the observed behaviors of subatomic particles is a famous idea of Hugh Everett’s to the effect that the universe of our experience is one of an infinite and endlessly branching collection of similar universes — and that what resistance there is to this idea is attributable to the influence of this or that fancy, misguided philosophical critique of good, solid, old-­fashioned realistic attitudes toward what scientific theories have to tell us about the world. This is simply, wildly, wrong. Most of the good, solid, old-fashioned scientific realists who take an interest in questions of the foundations of physics — like me, for example — are deeply skeptical of Everett’s picture. And that’s because there are good reasons to be worried that Everett’s picture cannot, in fact, explain those behaviors at all — and because there are other, much more reasonable-­looking proposals on the table, that apparently can.

Deutsch’s enthusiasm for the scientific and technological transformation of the totality of existence naturally brings with it a radical impatience with the pieties of environmentalism, and cultural relativism, and even procedural democracy — and this is sometimes exhilarating and sometimes creepy. He attacks these pieties, with spectacular clarity and intelligence, as small-­minded and cowardly and boring. The metaphor of the earth as a spaceship or life-­support system, he writes, “is quite perverse. . . . To the extent that we are on a ‘spaceship,’ we have never merely been its passengers, nor (as is often said) its stewards, nor even its maintenance crew: we are its designers and builders. Before the designs created by humans, it was not a vehicle, but only a heap of dangerous raw materials.” But it’s hard to get to the end of this book without feeling that Deutsch is too little moved by actual contemporary human suffering. What moves him is the grand Darwinian competition among ideas. What he adores, what he is convinced contains the salvation of the world, is, in every sense of the word, The Market.

And there are moments when you just can’t imagine what the deal is with this guy. Deutsch — notwithstanding his open and anti-authoritarian and altogether admirable ideology of inquiry — is positively bubbling over with inviolable principles: that everything is explicable, that materialist interpretations of history are morally wrong, that “the only uniquely significant thing about humans . . . is our ability to create new explanations,” and on and on. And if the reader turns to Pages 64 and 65, she will find illustrations depicting two of them, literally, carved in stone. I swear.

Never mind. He is exactly who he is, and he is well worth getting to know, and we are very lucky indeed to have him.