Both 'the postulate of adequacy' (A. Schutz) and 'double hermeneutic' (A. Giddens) can be considered as critiques of positivism. I think positivism has two main components, the 'unity of science' and the 'rationality of science'. The 'rationality of science' is my coinage. It refers to the belief that scientific knowledge is rational and objective and much better than any other forms of knowledge epistimologically.
Traditionally some social theorists have critisized solely the idea of the “unity of science”. That has depended on the dichotomy of 'Geisteswissenschaften' and 'Naturwissenschaften'. Schutz and Giddens refute the “unity of science”, too. Their views can be seen as up-to-date styles of criticism on positivism. But I argue that their critiques do not necessarily succeed. So I will suggest that to gain the post-positivistic self-understanding of sociology, sociologists must criticize not only the 'unity of science' but also the 'rationality of science' by reference to Feuerabend.