ABSTRACT
Karl Popper, Thomas Kuhn, Imre Lakatos and Paul Feyerabend have succeeded in making irrationalist philosophy of science acceptable to many readers who would reject it out of hand if it were presented to them without equivocation and consistently. A scientific theory, Popper never tires of reminding his readers, is never certain in relation to, or in other words deducible from, those propositions which constitute the reasons to believe it. Popper endorses the notorious sceptical thesis of David Hume concerning inductive arguments, or arguments from the observed to the unobserved. Popper's philosophy of science is at any rate not more irrationalist than that of Feyerabend, Kuhn, or Lakatos, and at the same time, as a matter of well-known history, Popper's philosophy owes nothing to theirs, while Kuhn's philosophy owes much to Popper. Feyerabend and Kuhn made some slight additions to their irrationalist inheritance; Lakatos made some trifling abridgments of it, as though he were slightly uneasy about it.
