 Thesis I reversed the direction of interpretation which the positivists had presupposed. Instead of meaning seeping upwards from the level of experience (or the observation-language), Feyerabend had it trickling down from theory to experience. For him, theory is meaningful independently of experience, rather than vice-versa. The roots of this view clearly lie in his contextual theory of meaning, according to which meaning is conferred on terms by virtue of their participation in theoretical contexts. It seems to imply that there is no principled semantic distinction between theoretical terms and observation terms. And Feyerabend soon followed up this implication with his “Pragmatic Theory of Observation”, according to which what is important about observation-sentences is not their having a special core of empirical meaning, but their causal role in the production and refutation of theories. 