I had a really strange dream experience the other night, which I don't think I've known the likes of before. It wasn't crazy or outlandish-- quite the contrary-- I had to do some math! Err, well, I didn't quite solve Fermat's last theorem. It was a pretty mundane dream where I was at a store eating some ice cream with friends, when the cashier demanded a tip on the $18 fare. After some arguing I agreed to pay him 15%. In normal thoughtless dream fashion I gave him a ten, but I suddenly realized that was way too much-- so I actually went about doing the calculation of 15%, moving the decimal over one place then adding half of that. OK, so maybe it sounds really stupid that I'm mentioning this. It was just weird that I actually broke out of the normal, vapid kind of dream state and actually consciously followed the steps for a computation in a dream. Perhaps a little less trivially, lately I've been having dreams where I find myself framing (though not solving! ) the philosphical arguments for the problem of consciousness. What I'm wondering is, has anyone else experienced these kind of 'intellectual' dreams? It's a new experience for me to actually be doing some kind of credible, critical thinking in a dream, rather than drifting around in strange environments and social situations (although I must say that in waking life I spend a lot of my time calculating tips and pondering the problem of consciousness, so maybe it's just a bit of stereotyped behavior). I've heard of mathemeticians and the like getting groundbreaking insights in dreams, but all those accounts make it sound more like some critical insight is suddenly revealed to the dreamer, rather than the dreamer consciously deliberating about the topic in a logical fashion.