Today we considered the falsificationism of Karl Popper. As we saw, Popper addresses himself to the problem of induction insofar as it is a problem for science. Hume pointed out that the method of induction cannot be proved using either induction or deduction. Popper argued that that is not a problem, because science proceeds deductively anyway. Scientists propose theories or exceptionless laws. Hume and others wrongly supposed that scientists generate these from experience. In truth, it does not matter how they come up with them. Instead of trying to prove that they are true, scientists then try to disprove, or falsify them. When a particular example conflicts with a general law, we can tell deductively that the law does not hold. Popper thought that only methods that proceed in this way can be real science (as opposed to pseudoscience, e.g. astrology).
I proposed that this addresses four things that motivated Popper. (1) Hume and (2) the philosophers of the Vienna circle, whose views Popper avoids by proposing a philosophy of science that is deductive. (3) Marxism. Popper’s lack of interest in the origin of scientific theories or laws is at odds with the Marxist emphasis on class. (4) Psychoanalysis. Popper’s criterion that all science must be falsifiable rules out pseudosciences that are always right, like psychoanalysis.
We saw Popper respond to an interlocutor whom he invents, the conventionalist. The conventionalist questions Popper’s claim that his science is deductive, by pointing out that Popper is always bringing assumptions into his deductions, for example the assumptions that the experiment was successful and not anomalous. Popper admits that the actual practice of science often does depend on things other than deduction, for example such assumptions and even just on common sense.