Mohammad asked:

What is a 'refutation' in Popper's view?

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One of Popper's books is called Conjectures and Refutations. A conjecture is a proposed theory of
how some scientific thing works. A refutation is an experiment that does not turn out the way it was
predicted to, on the basis of the conjecture. It falsifies the theory.

Tim Sprod

According to Popper, the theorist is notobliged to treat every experiment which fails to turn out as
predicted as a 'refutation'. If the theory in question has made lots of successful predictions in the past,
then an alternative, less radical course of action is to put forward auxiliary hypotheseswhich explain
why the prediction failed in this particular instance. And that's where things get difficult. Because it is
left to the judgement of the researcher in each case of a putative 'refutation' whether to trash the
theory or try to save it.

Geoffrey Klempner

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