Difficult question. In terms of the things I’ve been interested in, Alan Turing and Gottfried Leibniz are probably the closest. But in terms of personality, they were very different from each other, and, I think, from me. I’m basically a “long projects” person: I work on projects for decades (Mathematica, Wolfram Language, Wolfram|Alpha, A New Kind of Science,…). Alan Turing, for example, was more of a “short projects” person: he’d work on one topic for a couple of years, then move on. Of course, one of his “topics” was inventing the idea of universal computation, which later on turned out to be a hugely big deal.

Leibniz was more a “long projects” person. He spent decades trying to perfect his mechanical calculator, and he pursued his idea of a universal language for representing everything (something I’m also very interested in) for much of his life. It’s a little hard to connect with his life: he spent a lot of it wearing an oversize wig, and hanging out “at court” trying to persuade dukes etc. to support his projects. I think I would fail “at court” very quickly: I’m much more of an entrepreneur who just makes things happen myself; I’d be horrible at lobbying to get a government or whatever to do things.