I've read, but forgot where, that grinning -- not exactly laughter, but a related act -- is also related to aggression or has its roots in it. It's hard to deny exposed teeth in a wide green -- think chimpanzee -- look at least slightly threatening.
I find it sad that not many people seem to laugh genuinely. So many people do the fake laughter, wiping away imaginary tears, at things which just aren't funny but which they seem to think they should appear to find really funny in a group.
Not to be nitpicky but I would say there are definitely situations where laughter is not a positive (edit: or beautiful) thing – laughing at someone else's misfortune, laughing in pain, etc.
> humor is related to strength. To have a sense of humor is to be strong: to keep one's sense of humor is to shrug off misfortunes, and to lose one's sense of humor is to be wounded by them.
I just have to say that i have had a word stuck on the tip of my tongue for an embarrassingly long time, maybe six months now. I’ve had occasion to use it several times recently on a project but it was just stuck wherever words get lost. I’m cruising HN in a post completely unrelated to what I’m doing and there it is, in living color: isomorphic.
I could feel the tension release in my brain as it sunk in. Thank you!
In the process of laughing together, our bodies move in time, which synchronises our muscle movements, which synchronises our heartbeats.
Yes, laughter is very powerful, and is a wonderful force for good in the universe :)