society of chimpanzees where a few individuals kill most of the others doesn't sound like a good survival strategy, so they are insane. In other species, such as sharks, which eat each other before they're born, it might be perfectly healthy. Ooh, it's gone all serious! OK, just to prove I'm not abnormal, so shall I. I've never been comfortable with the term 'mental illness'. It's one of those nice labels that is used to easily explain away people who think differently. This is often because of some chemical difference (or imbalance if you want to get subjective about it) in their physiology but I doubt if anyone can give me a definition of what 'mentally healthy' is. I do like the term 'mad' though as this seems rather more appropriate in that it really describes our (i.e. the allegedly sane) reaction to persons whose thought processes seem incomprehensible or unsettling. It's really a question of the majority imposing their values of what is 'normal' upon the whole population, most of whom would probably agree with the statement that "we are all individuals". Oh. Wow. Way too much for me to read. I was just going to point out that I posted pretty much this exact idea a while back (see link). The mechanism is subtly different, so I leave to the admins, if they're awake, to figure out whether that makes this one redundant. I think this is different, because with the other idea it is people you know,