„In the last few years I have been advocating a methodology of scientific research programmes, which solves some of the problems which both Popper and Kuhn failed to solve.
First, I claim that the typical descriptive unit of great scientific achievements is not an isolated hypothesis but rather a research programme. Science is not simply trial and error, a series of conjectures and refutations. ‘All swans are white’ may be falsified by the discovery of one black swan. But such trivial trial and error does not rank as science. Newtonian science, for instance, is not simply a set of four conjectures—the three laws of mechanics and the law of gravitation. These four laws constitute only the ‘hard core’ of the Newtonian programme. But this hard core is tenaciously protected from refutation by a vast ‘protective belt’ of auxiliary hypotheses. And, even more importantly, the research programme also has a ‘heuristic’, that is, a powerful problem-solving machinery, which, with the help of sophisticated mathematical techniques, digests anomalies and even turns them into positive evidence. For instance, if a planet does not move exactly as it should, the Newtonian scientist checks his conjectures concerning atmospheric refraction, concerning propagation of light in magnetic storms, and hundreds of other conjectures which are all part of the programme. He may even invent a hitherto unknown
planet and calculate its position, mass and velocity in order to explain the anomaly.“
Philosophical Papers, Volume 1: The Methodology of Scientific Research Programmes