 For the Positivists, earlier empiricists, such as Locke, Berkeley and Hume, had erred only in thinking that the mechanism of construction was mere association. But association can’t account for the structure of even a simple judgment, such as Caesar is bald. This is not merely the excitation of its constituent ideas, Caesar, is, and bald, along the lines of the idea of salt exciting the idea of pepper, but, as Frege had shown, involves combining the noun Caesar and the predicate is bald in a very particular way, a fact that was important in accounting for more complex judgments such as Caesar is bald or not bald, or Someone is bald. Our thoughts and claims about the world have some kind of logical structure, of a sort that seems to begin to be revealed by Frege’s proposals. Equipped with his logic, it was possible to provide a more plausible formulation of conceptual empiricism: our claims about the empirical world were to be analyzed into the (dis)confirming experiences out of which they must somehow have been logically constructed.