That freedom that Picasso afforded himself, to be an artist in a huge number of ways, seems to be a huge psychological liberation.
Everybody uses mime and gesture in real life, though we don't realize it. It's very useful as a performance technique, though it can be boring to watch on its own.
Writing is so wrapped up in ego, but with math one is just trying to get it right, although you're often wrong. I think math helped me become a good critic of myself, come at writing a little less personally.

