  According to Platonic versions of type realism, e.g., Bromberger 1989, Hale 1990, Katz 1981 and Wetzel 2002, the type is an abstract object, not located anywhere in space-time, although its tokens are.  This version appears to give rise to serious epistemological problems—we don't see or hear the type, it isn't located anywhere in space-time, so how do spatiotemporal creatures such as ourselves know it exists, or what properties it has? Admittedly, we see and hear tokens, but how are they a guide to what the type is like? One answer, given for example, by Wolterstorff, for whom we saw in §4 that a type is a norm-kind, is that ordinary induction from tokens would give us knowledge of types, at least in the case of instantiated types.  Bromberger (1992a, p.176) claims that linguists “often impute properties to types after observing and judging some of their tokens and seem to do this in a principled way” and calls the principle that licenses this inference the Platonic Relationship Principle. More specifically, he proposes (1992a) that the type, as the archetype of the quasi-natural kind which comprises the tokens, has just those projectible properties that all the tokens have. He has in mind properties such as the same underlying phonological structure, for words, and the same boiling point, for elements.