I certainly have no option but question for example Togo’s or Fast’s notion of "abstraction" because I think what they seem to mean doesn’t appear to exist at all. Why spend time considering what the notion of abstraction might be able to achieve if there is no reason to believe there is any abstract thing?
Ah, I should have been clearer. It's worth spending time on it because as a result we may conclude that a strictly physical representation of the universe is inadequate. That doesn't commit us to whether or not it's true - one can always postulate the existence of hitherto undiscovered mechanisms to make all apparently immaterial things material (or vice versa) - but it is relevant in deciding whether, given our present understanding and knowledge, it is more accurate to call the universe material, immaterial, or a mix of the two.