Imre Lakatos. 1970. “Falsification and the Methodology of Scientific Research Programmes.” In Criticism and the Growth of Knowledge, edited by Imre Lakatos and Alan Musgrave, 91-195. Cambridge: Cambridge University Press. Parts 1, 3.0, 3a-b, 3d.0, 3d.4, and 4.
The history of science has been and should be a history of competing research program (or, if you wish, ‘paradigms’), but it has not been and must not become a succession of periods of normal science: the sooner competition starts, the better for progress. ‘Theoretical pluralism’ is better than ‘theoretical monism.’ But budding research programs should be given time to develop and compete with more established, powerful rivals. Purely negative, destructive criticism, like ‘refutation’ or demonstration of an inconsistency does not eliminate a program.