In this paper, I argue that pluralism about material constitution (i.e., holding that the relata of constitution can be non-identical) is a theoretically useful notion. First, I propose a principle whose denial is sufficient and, to my knowledge, necessary for pluralism to be true. Then I formulate three metaphysical antinomies (the problem of material constitution, the problem of change, and the problem of many) in such a way as to reveal that the previous principle is involved in all three. Then I show that the denial of the principle resolves all three of these problems. Finally, I conclude that pluralism is indeed theoretically useful on the basis of the following three points: 1) denying the mentioned principle is sufficient for pluralism to be correct, 2) denying the principle resolves three problems, and 3) by a theoretically useful notion I mean that if it were true it would solve multiple problems.