 This does not avoid all controversy. Early set theorists and an array of contemporary metaphysicians reject the empty set. Yet the loveliness of the construction makes many of their colleagues receptive to Wesley Salmon’s ontological argument: “The fool saith in his heart that there is no empty set. But if that were so, then the set of all such sets would be empty, and hence it would be the empty set.” (Gardner 1977, 32).