As I was coming up with my own list of “influential” books and scanning some of the ones others picked, I got to thinking a bit about just what we mean when we say a book “influenced” us. People used the term in a variety of ways, but it seemed as though most of the variety could be mapped along two dimensions—let’s call them formal/substantive and theoretical/practical. Suppose I say I was influenced by Ernest Hemingway’s books. If I’m an aspiring novelist, I probably mean this in the formal/practical sense: I want to write novels like his, and will probably turn out a lot of painful stuff full of terse declarative sentences. But I might have a more substantive influence in mind: I’ve adopted a particular kind of vision of masculine virtues with a premium on physical courage, “grace under pressure” and so on. Where that falls on the theoretical/practical dimension depends on whether I actually take up bullfighting or enlist in someone else’s civil war.
Slightly less fanciful: Suppose someone lists Milton Friedman’s Capitalism and Freedom as an influence. At the formal end, an economist whose interest in the discipline was sparked by reading Friedman as a kid might say this even if he later came to disagree with all of Friedman’s specific policy views. A little further down, you might come away with a general view about the virtues of unregulated markets, and further still, with a specific conviction about (say) school vouchers. Of course, you might simultaneously be influenced in all these ways—and indeed, it would be hard to imagine someone finding the particular policy argument compelling without adopting the middle-level view to some extent—which probably tends to obscure the different levels of influence involved. The theoretical/practical dimension is especially fuzzy for writers and academics, for whom there’s not as clear a division between “what you think” and “what you do.” But even for us, I think there’s a rough distinction between adopting a belief and adopting a habit of thought. So if I’m a columnist who’s been persuaded by Friedman’s mid-level view of the virtues of lightly regulated markets, a more theoretical form of influence might be that I’m disposed to invoke Friedman’s arguments in a political debate—to assert certain kinds of propositions—while in a more practical mode the same arguments might function as conceptual tools I use to understand a new issue more than statements I’m prepared to endorse. In terms of the old Zen koan about the finger pointing at the moon, you might call this the difference between looking at the finger and following it to the moon.
You can pick a bunch of different types of books and try to imagine what the different forms of influence might look like at different points of this schema. Say Miles Davis’ autobiography. Formal/Theoretical: I get interested in reading more about the lives of artists and musicians, or the history of jazz. Formal/Practical: Miles dealt with all sorts of personal hardship, and I take away lessons for my own life from that. Substantive/Theoretical: I have a richer appreciation of Miles’ music because I have a fuller understanding of the context of its creation. Substantive/Practical: I want to be a jazz trumpeter (and either try heroin or stay far the hell away from it).
Anyway, I wanted to toss this out there mostly because I noticed that the books I picked were mostly influential somewhere around the middle of both axes. In other words, they were books that I found I could strip-mine for a lot of handy multipurpose conceptual tools I find myself applying in a variety of contexts. So the important thing about Code wasn’t that it convinced me to take a particular position on (say) intellectual property laws—though it probably did that to a degree, in tandem with a bunch of stuff I read later—but that it got me interested in thinking about certain categories of issues in a particular way. So looking over other people’s lists, while of course it’s revealing to learn which particular books people named as influences, it’s also interesting to infer from what people say about them how they tend to be influenced by books. Now maybe someone can flesh out this schema and write a meta-influential book that influences the way people are influenced by other books.