12 September 2009

Imre Lakatos

Our next reading for Philosophy of Science comes from Imre Lakatos. This reading made a lot more sense to me than any of Kuhn's stuff. As it turns out, Kuhn argues strenuously that his theory of science is not a stepstone to post-modernism, but most people who look at it think it makes even less sense taken that way.

This article compares Kuhn, Lakatos, and Laudan (whom we haven't read yet). Wikipedia has a decent summary of Lakatos's ideas:

The scientists involved in a programme will attempt to shield the theoretical core from falsification attempts behind a protective belt of auxiliary hypotheses. Whereas Popper was generally regarded as disparaging such measures as 'ad hoc', Lakatos wanted to show that adjusting and developing a protective belt is not necessarily a bad thing for a research programme. Instead of asking whether a hypothesis is true or false, Lakatos wanted us to ask whether one research programme is better than another, so that there is a rational basis for preferring it. He showed that in some cases one research programme can be described as progressive while its rivals are degenerating. A progressive research programme is marked by its growth, along with the discovery of stunning novel facts, development of new experimental techniques, more precise predictions, etc. A degenerating research program is marked by lack of growth, or growth of the protective belt that does not lead to novel facts.

As the comparative article points out, not all of Lakatos's criteria are well-defined, yet I found myself nodding agreement through our reading from Lakatos, so I think he's onto something even if it needs to be fleshed out more. The problem with strict Popperianism is that, given a refutation, scientists usually don't throw out the overarching theory, but instead try to adjust it. Popper seems to say that such adjustments are always ad hoc and to be avoided. Lakatos says that if such adjustments lead to novel predictions independent of the monkey wrench that induced them, then there's no problem with them. For instance, variations in the observed orbit of planets resulted in the hypothesis that there was another large planet in the solar system. The result? Neptune's existence was predicted, and it was later found. That didn't work so well with Mercury's orbit, though a similar tack was tried.

The question for a strict Popperian is why, when it failed to find an explanation for Mercury's orbit, was Newtonian gravity not abandoned. Lakatos has a partial answer: an overarching theory won't be abandoned unless a rational alternative exists. Thus Mercury became an "unsolved problem" until Einstein's modified theory of gravity came to the fore. Still, note that Einsteinian gravity theory has not really replaced Newtonian gravity theory. In most frames of reference, Newton's methods give accurate enough results. When more precision is needed, or in cases where relativistic effects become significant, then Einstein's version is used.

I may have more to say about Lakatos later, but I found that he's also contributed quite a bit to the Philosophy of Mathematics. Non-Deductive Methods in Mathematics gives a taste of his work there.

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