“What I’ve always believed is that humanity has the capacity to be kinder, more just, more fair, more rational, more reasonable, more tolerant. It is not inevitable. History does not move in a straight line. But if you have enough people of goodwill who are willing to work on behalf of those values, then things can get better. America as an experiment is genuinely important to the world not because of the accidents of history that made us the most powerful nation on Earth, but because America is the first real experiment in building a large, multiethnic, multicultural democracy. And we don’t know yet if that can hold.”
There's a lot in this article that had me thinking, but here's one thing that I think sums up Obama better than anything else he said: he's always looking to make things better. What your definition of better is may differ from his, but that feels like a fundamental way he operated while in office.