Richard Marshall interviews Massimo Pigliucci in 3:AM Magazine:
3:AM: Philosophy of science is a big interest for you. Science vs religion has been making headlines but you’ve recently written about the demarcation problem – the issue about how we make the distinction between science and pseudo-science, and this strikes me as being as equally problematic and important as the atheist vs believer dispute. This is something Karl Popper discussed and Larry Laudan more recently too. Before saying why aren’t they the last word for you can you briefly introduce us to how they tackled the issue?
MP: The term “demarcation problem” was introduced by Popper, and it refers to the issue of what, epistemically, separates science from non-science and pseudoscience. Popper was interested in it because of his concept of falsificationism – the idea that the reason science makes progress is not (as popularly believed) because certain theories are confirmed to be true, but rather because some theories are falsified (and permanently discarded) when they fail the empirical test. For Popper, that is, real science advances not by accumulating truths, but by eliminating falsehoods. So, for instance, Popper thought that Einstein’s theory of relativity was good science (it could be shown to be wrong, in principle), while Marxist theories of history, or much of psychoanalysis, is not (since the “theory” can be constantly adjusted by its supporters to fit whatever data may come in).
Laudan, in a very influential paper published in the early ’80s, pointed out that philosophers of science had long abandoned simple falsificationism (it doesn’t work as neatly as Popper thought, because of something called the Duhem-Quine thesis – more on this another time?). Laudan further argued that it is pointless and dangerous for philosophers to engage in demarcation projects. Pointless because it is not possible to come up with a sharp definition of science (or pseudoscience), dangerous because making public pronouncements about the rationality or irrationality of a given belief or practice has serious social consequences.
More here.