Some notes on the comments I made here, inspired by correspondence.
Note 1: My comment was original in the sense that I didn’t pick it up from anywhere. However, its by no means a philosophical leap and so I would be shocked if no one has asserted it, even if there is some straight forward demonstration that it is wrong.
Note 2: When I say causality is superfluous I mean that it is not a meaningful metaphysical construct. Either you are talking about something plainly physical or you are talking about nothing.
You may be simply making a description of space-time. So if I say: “the cue ball hit the eight ball and caused it to move.” I may simply be describing the shape of these objects through time.
This is the same kind of statement as: “The camera is on the table”
We can further talk about the “statics” underlying the camera being on the table. Or we can talk about the “dynamics” of the cue ball hitting the eight ball. However, these are all generalizations of observations we have regarding objects in space-time.
And, importantly the generalizations are derived from objects that we have in fact experienced.
On the other hand, if you mean that there is some sort of metaphysical necessitation such that when cue balls hit eight balls the latter must move. And, further that this metaphysical necessitation may be hidden from us (ala David Hume) then you are speaking of nothing.
When people utter the words “the cue ball caused the eight ball to move” they are usually providing a description of how they feel about the cue ball and the eight ball.
And, the reason that confirmation of this statement alludes us is because there is no truth to be had outside of the mental and emotional state of the speaker.
Note 3: None of this is to say that we can’t apply the term causation to our generalizations about the shape of objects through time. It is simply that this re-defining strips away any metaphysical specialness associated with the term.