A trick to using malapropism is to ensure that the two words (the original and the substitute) sound similar enough for the reader to catch onto the intended switch and find humor in the result.
Positivism is a philosophical theory stating that positive knowledge is based on natural phenomena and their properties and relations. Thus, information derived from sensory experience, interpreted through reason and logic, forms the exclusive source of all authoritative knowledge.
Constructivism is an emerging field in international political economy. In general, the constructivist view propounds that material interests, which are central to liberal, realist, and Marxist views, are not sufficient to explain patterns of economic interactions or policies, and that economic and political identities are significant determinants of economic action.