So there's this supposedly an 'interaction' problem for substance dualism, that isn't there for physicalism or idealism. I've never understood this.
So as Hume pointed out, we see event a followed by event b. We don't see a link connecting event a and event b. We impute a cause-effect relationship to the two events. All we have are datapoints with event a followed by event b. That's it. Based on that, we create equations that model what happens in the physical world, and we try to falsify those models We don't have an "explanation" of physical causation. We have models/equations... and data fit those equations or don't. We don't ask for further explanations. Why is it problematic if event a has a different ontology from event b?
Imo, we should simply do the same thing we do with physical-physical interactions... take the datapoints of mental events followed by physical events or vice versa... create models and try to falsify them.
There may be other valid arguments against mind-matter interaction, but what I'm attacking here is the kind of a-priori incredulity that's presented in these discussions, as if there is absolutely no mystery as to how matter should interact with matter... but mind interacting with matter is some kind of unbridgeable gulf.
It would be similar to someone asking "How is it that massless photons can have momentum?" I'm not sure what kind of answer would be expected... the laws of physics allow it?