The positive heuristic of the programme saves the scientist from becoming confused by the ocean of anomalies.

Intellectual honesty consists in stating the precise conditions under which one will give up one's belief.

Research programmes, besides their negative heuristic, are also characterized by their positive heuristic.

That sometimes clear ... and sometimes vague stuff ... which is ... mathematics.

One may rationally stick to a degenerating research programme until it is overtaken by a rival and even after. What one must not do is to deny its poor public record... It is perfectly rational to play a risky game: what is irrational is to deceive oneself about the risk.

Mathematics does not grow through a monotonous increase of the number of indubitably established theorems but through the incessant improvement of guesses by speculation and criticism, by the logic of proofs and refutations.

If even in science there is no a way of judging a theory but by assessing the number, faith and vocal energy of its supporters, then this must be even more so in the social sciences: truth lies in power.