From an in-depth look at runaway universalism:
In most societies across the world (i.e., clannish ones), there are weak and highly conditional attitudes towards reciprocity. The primary targets of altruism are kin. Prosociality is maintained through various forms of social honor and shame or at worst, fear of reprisal from the aggrieved or by the state. Dealings between non-kin typically take place warily and with many measures to ensure honesty by all participants. Trust is very low and is not given freely.
By contrast, NW Europeans have evolved a sense of reciprocal altruism and can deal much more readily with non-related individuals. Trust is extended. The other party is presumed to act honestly. Indeed, favors will be extended to others because the recipient may one day return the favor (or at the very least, the helping individual may earn a reputation for generosity that may parlay into favors from others).
…Having a sense of reciprocal altruism (which actively seeks targets with which to trade favors) â€“ along with a suite of other traits that co-evolved with this (such as a sense of fairness and a belief in the equality of all in-group members) â€“ there is little to prevent extending the (soft) cognitive barrier those presently in an outgroup when new information serves to humanize this outgroup (by appealing to affective empathy). And since no outgroup is really any different from any other (being effectively equally unrelated), thereâ€™s nothing to stop this process from repeating once new outgroups become humanized. Runaway universalism was thus inevitable.
Universalism, or the idea that every person is equal and therefore the same methods can be used on all people, seems like it would arise from this reciprocal altruism turned into promiscuous altruism. However, there is an elephant in the room.
All human civilizations so far have gone out after achieving success. With this success came primary factors of Progress, like industry and universalism. Secondary factors like diversity and instability were both symptoms and direct causes of the disintegration.
Universalism arises from socializing. When you hang out with other people, the correct way to make them happy is to emphasize a sense of group togetherness. This requires including all of these people without looking too deeply into their failings. This is why successful societies develop universalism: what we call bourgeois values are in fact commercial values, which are social values, and demand equal inclusion which produces universalism.
From this comes the altruism we see, because altruism is a virtue signal for universalism.
Not to ruin an excellent analysis by Jayman, but if we look at the psychology involved, we can see he has the causality backward. The societies that succeed adopt a commercial/social mentality and it is what kills them. As we are starting to see, Progress and formalization are a death-trap, and these arise from the same impulse.
Unsurprisingly it also brings altruistic universalism that pervasively infiltrates our minds, starting with the smartest. This explains why civilizations succeed and then self-destruct, not the other way around.