[originally from December 21st, 2014]
There are couple of things humans are generally good at. For example, reciprocating, and in particular – reciprocating hostility. Maybe not everyone is gonna be grateful for good things (although Cialdini says that most are), but nearly everyone will be at least sightly mad at those who are mean to them. This makes sense from the perspective of strategy – however strongly you want to make friends, you don’t wanna be attacked to hostile entities. In addition, humans are good at finding patterns, and generalizing from examples. This may not be the epistemologically optimal way to learn from sensory information, but it’s definitely better than not attempting to generalize, and memorize every know instance of a phenomenon separately. And finally, humans are very good at identifying with groups, and taking individual offence over the attack on the group, which is obviously useful for cooperation. These skills are so crucial that they occur completely subconsciously, sometime even against the conscious will.
This is how ethnic tensions escalate. There are two groups – X and Y. They don’t even have to differ all that much, although it “helps”. A subgroup x is hostile to Y. Naturally and justifiably, Y gets mad at x – in fact, the rest of X may get mad at a too if they are peaceful enough. But the crucial part is that a subgroup y appears, who’s not just mad at x, but at the whole X – and they’re hostile to them. Most of non-x members of X will only get mad at y, but some of them will get mad at the whole Y, thus joining x. Thus, the feedback loop appears, and tensions escalate. Sometimes all the way up to a war, and this is a rather textbook example of how that happens.
Thus, if someone claims that despite decades or even centuries of the existence of X, x, and Y, y doesn’t exist, I’m extremely dubious about this claim. If that’s the case, it goes against the common trend, which requires some explanation. Especially in the case when there appears to be some evidence that y exists.