Here's a thought:
Cross-training is well-established in athletics. To be a really great baseball player, say, you're going to spend at least some of your training time doing things that aren't directly baseball-related. But it's a broader principle than that: it's a rare juggler who just juggles the type of prop he performs with. Paul Graham writes about
how his painting improved his hacking. And so on.
So why don't academics do it? Mostly, we seem to pick a specialism and then largely ignore anything outside it, at least professionally. There are counterexamples: one of the lecturers in my department is half-way through a degree in Russian. And a lot of the really great intellects - Wittgenstein, Feynmann - seem to have been able to turn their hands to anything.
I guess this is something like the US idea of a minor at college. Someone (possibly Donald Knuth) reckons that in the near future, every academic will have a major and a minor specialism, but he's thinking of this as a way of coping with the complexity and scope of modern science - we won't find the fertile connections between field A and field B if the only people who know about field A know nothing about field B and vice versa - whereas I'm thinking of it as a way of improving our minds.
So, what do you all think? Good idea? Or should I go and have some more coffee until I've calmed down a bit? Are there any other good ideas that academia could take from sports? From somewhere else?