Without a priori synthesis, empirical representations would be of objects that are indeterminate with respect to multiple possible ways of conceptualizing and individuating them.

For Kant, a defining feature of our representations of objects is their objective validity. For a representation to be objectively valid it must be a representation of an objective feature of reality, that is, a feature whose existence and nature is independent of how it is perceived (Guyer 1987:11–24). In this argument, it appears that Kant just assumes that the representations that make up experience are objectively valid. He then aims to establish that association is inadequate because it can