Positivism

… the claim that Popper was a positivist is a common misunderstanding that Popper himself termed the "Popper legend." In fact, he developed his views in stark opposition to and as a criticism of positivism and held that scientific theories talk about how the world really is, not, as positivists claim, about phenomena or observations experienced by scientists. In the same vein, continental philosophers like Theodore Adorno and Jürgen Habermas regarded Popper as a positivist because of his alleged devotion to a unified science. However, this was also part of the "Popper legend"; Popper had in fact been the foremost critic of this doctrine of the Vienna Circle, critiquing it, for instance, in his "Conjectures and Refutations".