The fox and the hedgehog

The Greek poet Archilocus originated the expression “the fox knows many things, but the hedgehog knows one big thing.” But it’s philosopher Isaiah Berlin who popularized the expression in a famous essay dividing writers and thinkers into “hedgehogs” and “foxes”.

As this blog’s header pictures and tagline illustrate, I like to think of myself as a fox, and not just as a silly pun on my last name. I like to think of myself as someone who reads and thinks broadly, and who has lots of medium-sized ideas rather than one big idea. Indeed, I’ve made a conscious effort to stop thinking about my biggest idea (applying the Price equation to ecology), lest I start violating my own advice. I feel like this breadth makes my research program robust; it’s not as if everything I’ve done will come crashing down if any one idea of mine is found wanting.

Of course, there are advantages to being a hedgehog. If your one big idea is something like evolution by natural selection, or general relativity, you’re an immortal*. Which is something I’m never going to be. And all scientists are more specialized and hedgehog-like than they used to be. The last person who knew pretty much everything there was to know about everything was probably Leibniz.

But am I really a fox, even judging by today’s standards of fox-ness? One could certainly argue that I’m not. Almost all of my own empirical work is in one deliberately-simplified artificial system. All of my work shares a particular approach to science: it’s all fundamental, question-driven research, mostly based on developing and applying simple dynamical models. Until recently, I’ve only had a small number of collaborators, all of of whom basically share my point of view. All of which would seem to make me a hedgehog (or even a one-trick pony) rather than a fox.

And I’m sure I’m not uniquely difficult to classify. Take the great David Tilman. Is he a hedgehog, because of his career-long focus on resource competition? Or is he a fox for seeing the relevance of that idea to systems ranging from algae to grassland plants, and to problems ranging from species coexistence to climate change to weed control to ecosystem function? If forced to choose I’d say “hedgehog”, but I can see where others (quite possibly including David himself!) would legitimately disagree.

Similar questions can be asked in other fields. Andrew Gelman suggests that statisticians are mostly foxes, because they all work on lots of different problems. But then again, if you focus on one method that you apply to all those problems, like Galton with regression or Pearl with SEMs, doesn’t that make you a hedgehog?

Maybe the right conclusion to draw is that most successful scientists have elements of both the fox and the hedgehog.** If you really don’t have any “core” ideas or convictions that underpin or tie together everything you do, then you’re not a fox so much as a dilettante. But conversely, if you really do know just one thing, then unless that one thing is really big, you’re just narrow.

As a scientist, do you think of yourself as a hedgehog or a fox? Who are the great “foxes” and “hedgehogs” among ecologists?

*Not that Darwin and Einstein didn’t have other ideas; I’m just using their biggest ideas as examples of single ideas that, on their own, comprise massive contributions to science.

**I say “most” because I think Paul Erdös was a pretty inarguable example of a pure fox.