Leigh writes: When I was a PhD student in philosophy, I did a lot of work in philosophy of science. Not science proper, but after all, philosophy was (and is) the beginning of science. ;)Anyway, my tattoo is a riff on the history of both science and philosophy– the hermetic symbols for the Philosopher’s Stone (sulfur + mercury + salt, and some sort of time designation). Yep, that’s right, alchemy.