given all of the apparent disadvantages of the blind idiot God, evolution was able to come up with altruism, something that works two levels above the individual and one level above society.

Much human altruism is fictional - humans are nice to other humans mostly because being nice pays.

There are low-level selection explanations for most of the genuine forms of human altruism. IMHO, the most promising explanations are:

• Altruism is the result of manipulation by other humans;
• Altruism is the result of manipulation by memes.
• Altruism is the result of overgeneralisation due to cognitive limitations;
• Altruism towards kin (and fictive kin) is explained by kin selection.