Just a lay person, but...

I think it's odd that the theory was "destroyed" by an argument using formal logic. It presupposes that a) humans are logical b) they act in a logical fashion c) if stealing is bad then murder is bad is not an opinion, and d) opinions can't be logically consistent (wtf?)

A 'logical' argument can be made for being homophobic: non-procreation is bad; hence, homosexuality is bad. Yet, a) not everyone who is homophobic uses arguments, because a bunch also just want to follow scripture, b) this can still be an opinion [1] and logically consistent. What happens in the real world, though, is that non-procreating/infertile couples do not face discrimination in the same way [2], and a homosexual might procreate and then raise the baby with a partner, and still face discrimination.

This does not explain cultural differences, and exceptions, and other arbitrary moral attributes (i.e. not 'logical' ones). If I can find a cross-cultural counter-example for something one culture deems moral, and both are equally logical in their claim, what does that say about logic? That is, to go meta-meta: why is something being logical good? Examples: if murder is bad, how are capital punishment and war good? How is a crime of passion excusable? Most importantly, how is being pious a marker for morality? If my culture thinks maximizing self-interest leads to maximum aggregate happiness, and another culture believes it comes from maximizing group interest, both are logically consistent arguments in and of themselves.

There is a (now famous) classroom experiment where the teacher said that blue/brown eyes were superior [3], resulting in kids treating each other in a generally shitty way. What I mean is: a) morality is tied to power, and that b) it is perfectly capable of producing a logical system that can be immoral. Take racism as an example, take the moral judgements of colonists as an example.

Notes: [1] Why is non-procreation bad? And have attitudes about the morality of an act changed? Does that mean a change of logic or of opinion?

[2]As an aside -- procreating has a high value placed on it in the Old Testament, for example, and G-d often promises prophets 'a nation', because there is no concept of heaven. Hence, this system is consistent in placing a value upon procreation.

[3] https://en.wikipedia.org/wiki/Jane_Elliott#The_first_exercise_using_brown_collars See also: Stanford Prison Experiment

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