If only we could all reset to the kind, trusting human nature.

That thought has been with me for a while. Spoilers for Joe Haldeman's Forever Peace, but he's explored the concept in a fiction setting where humans can directly connect their brains to each other with a plug in the back of the skull, to directly feel each other's feelings and body. They use it for sex and war machines, which is ridiculous at first, but then it makes sense.

But the protagonists discover that if you connect to another you become "humanized", and unable to do any harm whatsoever to any other human, seeing it as a damage upon one's self.

Pretty good book, would recommend.