(1) I’m not sure what natural kinds are if ‘being married’ is possibly one. SEP’s opening definition takes natural kinds to be properties independent of human behaviors and interests. So by definition, marriage isn’t a natural kind. (2) Given his characterization of natural kinds, I don’t see any opposition between a socially constructed kind and a natural kind. Just as ‘being married’ figures in explanations, allows for inductive reasoning, and captures similarities, the same might very well be said of kinds which are clearly socially constructed. ‘Being classmates’, for example. (3) I don’t see any reason whatsoever that anyone would accept his premise that ‘if marriage is a social construction then it’s defined in terms of the rights and responsibilities society ascribes to it’ (19:30). It seems obviously false. ‘Society’ isn’t some homogeneous entity which has assigned a fixed set of necessary and sufficient conditions for ‘being married’. In fact, his example of the pair of individuals, legally spouses who’s only interaction consists in throwing dishes at each other should work as a counterexample to his thesis. It is exactly because there’s room for disagreement as to whether they are married that marriage isn’t a natural kind. (4) His clearest case is probably the critique one. We can criticize bad spouses. But he hasn’t argued, and I don’t see how he would, that such criticism isn’t reducible to regular ethics.

He looks like Gregg Turkington.