[Jimmie]

It's twisted but I always wonder the same thing. Why don't psychopaths "get" more people? If someone rings my doorbell I answer the door, I expect the person on the other side to be a rational human being. It wouldn't be too hard for the other person to just bum-rush me with a knife and take me out.

I think there may be an evolutionary factor involved, easier to survive in a group so there is an incentive not to harm those around you. Able bodies can warn of nearby danger and help fight off threats, as long as you aren't a threat to them and they aren't a thread to you you're golden. There's also the fact that most people are fairly content in society and like things to stay relatively constant. Nobody wants to risk the rest of their life by doing something dumb like even accidentally injuring someone, let alone purposefully killing someone.

[InclinedPlane]

Psychopaths kill plenty of people though. But it helps that the vast majority of people are not psychopaths, and they react when someone does something like kill someone. If you murder someone in front of someone else your opportunities for surprise go out the window, and so much of our lives are lived in public (long stretches of private time notwithstanding). The other thing is that humans, even psychopaths, are sentient. They have feelings, they need a motivation, a reward for killing. And suicidally trying to kill as many people as possible is, in most cases, not in the cards, which is another limiting factor. If you took, say, 1 ppm of all humans on Earth and suddenly exchanged their brains for typical movie "monster rules" then things would get very ugly very fast, but not indefinitely, they would be contained, killed, brought under control by the majority of sane folks.

Nevertheless, look at folks like Ted Bundy who had a very specific target for his murders and yet still killed dozens of people in his life.

[barrkel]

Pyschopaths that twisted wouldn't get very far. It's the same thing with a disease; if it's very lethal and highly contagious, it's not actually very dangerous, because it will kill most carriers before it gets a chance to spread.

[Tycho]

Google 'Monster of the Andes'