1. It is hard to see how moral facts supervene on natural facts, because why would one atom bumping into another matter morally?
2. It is easy to see how moral facts supervene on facts about experience and intention. In any universe that has pain, deliberately causing pain is surely wrong
1 and 2 can only be true if 3 is true:
3. It is hard to see how facts about experience and intention supervene on favys about physics.
…which we ready knew. The relation between experience, qualia, and physics is the or a hard problem. We now can see that it’s hardness contributes to the hardness of understanding moral realism.
In fact we can make this three level structure mathematically precise: thecworlf of fact is the value free world. The world of aesthetics is the world of valuation of subjects, ie relations between entities with preferences and entities without. The world of ethics is reactions between two or more entities with preferences.