In Chapter 2 it was shown that Karl Popper’s notion of the nature of the philosophy of the natural sciences was from the outset directed critically against the logical positivism of the Vienna Circle; it was, as far as it went, an essentially antipositivistic conception in that sense. Popper’s antipositivism was not always fully understood, and many writers, including some logical positivists, continued to think that there was more held in common between him and the Vienna Circle than there was that divided them. In order to rebut this view, Popper could repeatedly remind readers that his proposal to demarcate science from metaphysics on the basis of the former’s falsifiability-in-principle was not, and was never intended to be, a theory of meaning, as logical positivism’s principle of verifiability was, and was not designed to demonstrate the meaninglessness of metaphysics. In this way, Popper’s antipositivism could be clearly and precisely delineated. However, in the course of this protestation of the purity of his antipositivism it was quite unnecessary to refer to his views on the social sciences and their methods. It is only since the Positivismusstreit, and the consequent emergence of the term ‘positivism’ as a shibboleth, that critical rationalism has had to define specifically its antipositivism in the context of the philosophy of the social sciences.