Short story: I'm going to be a Fusion Party candidate for Grayndler in the next Australian federal election. I even made a Facebook page and a Twitter account , and wrote a political ramble below. Regardless of what one thinks of Dunbar's number and the reasoning behind it, human brains evolved in the context of a small number of people. Maybe there were a hundred people in your group, and you knew people in a few other groups. If you even knew of the existence of a thousand people, you'd probably qualify as some kind of social butterfly. So it's mind-blowingly amazing that we've managed to organise ourselves into societies of millions. But because we can't grasp that many people we've had to rely on what I think of as cultural shorthand. We can't care about everyone as individuals and figure out what's best for each of them, so we instead rely on caring about ideas: religion, political ideology, nationalism, feminism, human rights, and so on.