It's not an over generalisation - some people really are stupid, borderline competent. I get to meet lots of them. Here is an example I was told yesterday - Woman gives birth at home, realises that she doesn't have anything for the baby, so grasps it by the ankles and walks down to the shops with the umbilical cord still attached between her and the dripping wet baby. Someone sees this and (rightly) calls an ambulance. This person isn't mentally ill - just daft. Trust me - there are lots and lots of very silly people out there, just because you don't meet them doesn't mean that they don't exist. Take the woman who smokes during the pregnancy because she *wants* a small birthweight child as it'll be easier to deliver. I met a few of them in my time as a nurse. They are mentally competent to make decisions. But are still idiots.