Human morality is mostly a justification mechanism, trying to give coherence to the actions we were going to do anyway.
Here is an even more Hansonian view that I think makes better predictions: the side-taking hypothesis says that morality is a social tool for deciding which side to support in a conflict between groups. Extended quote:
Here is a distinctive human problem that just might explain our distinctive moral condemnation: Humans, more than any other species, support each other in fights, whether fistfights, yelling matches, or gossip campaigns. In most animal species, fights are mano-a-mano or between fixed groups. Humans, however, face complicated conflicts in which bystanders are pressured to choose sides in other people’s fights, and it’s unclear who will take which side. Think about the intrigues of family feuds, office politics, or international relations.
One side-taking strategy is supporting the higher-status fighter like a boss against a coworker or parent against child. However, this encourages bullies because higher-ups can exploit their position. Another strategy is to form alliances with friends and loyally support them. Alliances deflate bullies but create another problem: When everyone sides with their own friend, the group tends to split into evenly matched sides and fights escalate. This is costly for bystanders because they get scuffed up fighting their friends’ battles.
Moral condemnation offers a third strategy for choosing sides. People can use moral judgment to assess the wrongness of fighters’ actions and then choose sides against whoever was most immoral. When all bystanders use this strategy, they all take the same side and avoid the costs of escalated fighting. That is, moral condemnation functions to synchronize people’s side-taking decisions. This moral strategy is, of course, mostly unconscious just like other evolved programs for vision, movement, language, and so on.
For moral side-taking to work, the group needs to invent and debate moral rules to cover the most common fights—rules about violence, sex, resources, etc. Humans are quite motivated to do just this. Once moral rules are established, people can use accusations of wrongdoing as coercive threats to turn the group, including your family and friends, against you [emphasis mine].
What the side-taking hypothesis suggests is that making the moral case for e.g. vegetarianism is a matter of convincing people to gang up against non-vegetarians in various ways, or rather convincing people that other people will do this. Insofar as you think this is bad, you might want to spread vegetarianism through a conduit other than morality.
Here is an even more Hansonian view that I think makes better predictions: the side-taking hypothesis says that morality is a social tool for deciding which side to support in a conflict between groups. Extended quote:
What the side-taking hypothesis suggests is that making the moral case for e.g. vegetarianism is a matter of convincing people to gang up against non-vegetarians in various ways, or rather convincing people that other people will do this. Insofar as you think this is bad, you might want to spread vegetarianism through a conduit other than morality.
Worth meditating on the side-taking hypothesis as it applies to the recent debacle around the vegan blogger who bought ice cream for a kid and got shamed by other vegans over it.