Wel, if you get into philosophy and the nature of being (as in Zen, various meditation techniques, etc.), you can find peace by accepting that things are the way they are because that's the way they are. Popeye says, "I am what I am and that's all what I am." - Very insightful for a fisherman, eh?
By recognizing that life contains no more meaning than what we give it (this isn't saying we can't understand why a tooth is the way it is, just that the way it is has no meaning beyond that's how it is, see?), we free ourselves from the shackles of what is to what can be (in Forum jargon, "creating in ourselves a clearing for the realm of possibility," though various religions and philosophies have their own terms for it).
That's cool, just not something they invented. It's cool because it brings many people peace when they recognize it: Maybe they're stressed about something, and realizing that thing is just what it is - that is has no intrinsic meaning beyond what you can actually do with it - it loses its power over us.