Pivoting off the "ten books" meme, Julian Sanchez "got to thinking a bit about just what we mean when we say a book 'influenced' us":
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.