Popper Proposed the criterion of falsifiability as a solution to the problem of demarcation i.e. of distinguishing science from pseudo-science and not, as many of his contemporaries in the Vienna Circle mistook it to be, a solution to the quite different problem with which they themselves were preoccupied, viz. of providing a criterion of meaning to distinguish the meaningful from the meaningless. While the positivists were concerned to damn metaphysics and exalt science, by identifying the empirically verifiable with the meaningful, Popper was concerned to separate science from scientism, to damn astrology and to extol astronomy. In other words his preoccupation belongs not to the philosophy of language but to the philosophy of science.