Earlier Schlick had argued that knowledge consists in the identification of that which is known with that as which it is known or, in other words, knowledge consists in the relation of one thing to some other thing, as which it is known. And this is only achieved when one of the objects which is known is, in turn, related to still others, as it is in the myriad spatio-temporal relations in which it stands to other objects. Ultimately, all these relations can be known quantitatively by specifying