[Tichy]

Wasn't there a story recently on HN about a guy who proved a longstanding open problem as a hobby, and was a security watchman in his day job? (Or some other job, I don't know).

I am surprised so many people here seem to lean towards "nature". I am pretty sure you can pick up mathematics at any age. Sometimes I also wonder: humans manage so many really complicated tasks in their daily lives, can it really be a much farther stretch to reach into mathematics?

Of course experience and knowledge and training help in mathematics, but as in other fields, maybe sometimes an outsider can bring a fresh view into it. It might also depend on the field of maths you choose, some might be more approachable than others.

That said, I agree with the other post that genius mathematicians are probably somehow born or made very early on.

[jeroen]

There was such a story ( http://www.haaretz.com/hasen/spages/966679.html ), but the guy was "an accomplished mathematician" before becoming a security guard.