Moral monism is the reduction of morality to a single principle (e.g. don’t do harm). Haidt argues this is unhealthy for society.
Is morality purely derived from reason? Or does one need to incorporate human nature (implying some of morality is innate)? Hume felt that those who use only reason to derive morality are not different from those who use sacred texts.
People fall under two axes: Empathizers and Systemizers. If you like fiction more than non-fiction, you are likely high on empathizing. If you are good at maps and instruction manuals, you are high on systemizing.
Autists/Aspergers are very low on empathizing and very high on systemizing. It just so happens that the leading ethical theories in Western philosophy were founded by people in this quadrant (Kant and Bentham).
Bentham and Utilitarianism
His utilitarianism was very precise. It actually involved summing of quantities.
Based on his biographies, he’s a good candidate for Asperger’s. He did poorly socially, and many did not like his company.
Kant and Deontology
Kant believed that morality should be the same for all creatures, regardless of their cultural or individual proclivities. Thus he felt deriving from observation would be tainted, and one should use reason alone.
Kant was also a loner, but people did like him socially. Probably did not have Asperger’s but still likely scored low on empathizing.