In this paper Peter Strawson’s idea of non-reductive analysis is illustrated with the example of an analysis of knowledge along the lines of my book on the ‘sandwich theory of knowledge’: Epistemologia. Sandwiczowa teoria wiedzy (Kraków 2019). On this theory, knowledge and justification are intertwined and relativized to the context that has been determined, on the one hand by pragmatic presuppositions, including idealizations and the ceteris paribus clause, and on the other by the intended scope of applications. Knowledge so conceived need not be true, which permits granting to the outdated knowledge an epistemic status different than that of mere superstition. Still, the mechanism of revision of presuppositions in the face of novel applications can be thought of as driven by the regulative idea of truth in Kant-Popper sense.