no particular set of propositions enjoys this privilege, that all sets are equally relevant. In that case, since every proposition coheres with some sets and fails to cohere with others, every proposition would be both true and false; and that is clearly untenable, for it flies in the face of the law of noncontradiction,14 which is itself necessary for rational discourse. So any attempt to avoid the question of which set of propositions is relevant to a given proposition’s truth by claiming that