C.3.1:2 - Problem
The sentence cooling pump is a pump is useful only when the membership conditions justify it. A current extension table can hide a bad proposal, and different intensional kinds can happen to classify the same candidates. Conversely, a unit rewrite, source move, or clearer declaration need not create another kind. The core needs an obtaining test for the relation and a before/after test for kind continuity without treating a signature, sample, locality, or extension as the kind.