One knows quite well that harmony can be a harmony of appearances - Paul Feyerabend

Facts are constituted by older ideologies, and a clash between facts and theories may be proof of progress.

Taking experimental results and observations for granted and putting the burden of proof on the theory means taking the observational ideology for granted without having ever examined it.

It is clear, then, that the idea of a fixed method, or of a fixed theory or rationality, rests on too naive a view of man and his social surroundings. To those who look at the rich material provided by history, and who are not intent on impoverishing it in order to please their lower instincts, their craving for intellectual security in the form of clarity, precision, "objectivity", "truth", it will become clear that there is only one principle that can be defended under all circumstances and in all stages of human development. It is the principle: anything goes.