Professor Strangelove

A few years ago it would have depressed me completely to admit that I read Philosophy for fun as well as profit; now I’m so innured to it that it just makes my start heart missing a beat and then I move on. I say this because I’m somewhat tempted to expand the blog to cover more than just Conspiracy Theories for the time being. I’m currently reading up on a whole host of subjects, most of which will get turned into Conspiracy Theory fodder, but it does mean that, unless I rehash old topics, I don’t have much to blog about (which could be seen as a good or a bad thing).

So, anyway, reductionism. It should be no great surprise to learn that I am a great fan of the Natural Science (points to those who can spot that partial quote) and of all the Natural Sciences I have to say that Physics is the one I would miss most if we had to give it up. The glorious part of Physics is that we can subsume Chemistry into it; Chemistry is the interaction of particles and the particles are described by Physics. Therefore Chemistry is a sub-domain of Physics (sorry Chemists; I realise I’ve just oversimplified that but bare with me). We would like to think that we could do the same with Biology; Biology deals with a special set of chemical compounds and we’ve already admitted that Physics covers Chemistry so surely Biology can be reduced down to Physics. For the first part of the Twentieth Century everyone believed that and things were looking good, until people started asking what the laws of Biology were. We knew about laws in Physics; Newton had a go at them, Einstein provided better ones and the String Theorists were generating all kinds of crazy. We knew about laws in Chemistry (and they all seemed to be laws about particle interaction, which sort of confirmed our previous assumptions) but Biology… Well, the laws looked statistical rather than general and they seemed to relate to very specific contexts, unlike the other scientific laws that we thought applied at all times and in all places (excepting just before and just after the Big Bang). In fact, we couldn’t even be sure that the things we thought true of Biology would be true anywhere else in the Universe other than the Earth.

Biology was beginning to look a bit peculiar.

Explanations in Physics and Chemistry are why-necessary explanations; they tell us why the event under consideration had to occur. Explanations in Biology are (usually) construed as being how-possibly explanations; they tell us a story (usually thought to be the best story according to the evidence) as to why the event under consideration might have occurred. Physics tells us what process produced the result we are looking at; Biology tells us that Natural Selection might well have worked in this way to produce that result. Why does a particular moth have Owl-like eye patterns on its wings? Because, over time, such markings were conducive to its fitness. The molecular biological why-necessary explanation that says ‘The spots are produced by the production of pigments A, B and C (which were caused by gene expression X, Y and Z)’ just doesn’t seem explanatory in the way that the how-possibly explanation of functional Biology does.

In the Philosophy of Science this suggests a problem. Either our account of reductionism (the ability to reduce theories down to their most elementary parts) is wrong or our construal of explanations in Biology is flawed. Most writers in the field (both in the Philosophy of Science and in Biology) suggest that the reductionist account needs modification; if our notion of theory reduction can’t accomodate what we take to be good practice in Biology then something is wrong with the (current) reductionist programme. Alex Rosenberg, in his book ‘Darwinian Reductionism: Or, How I Learnt to Stop Worrying and Love Molecular Biology’ goes the other way; the reductionist programme is a-okay and if we properly characterise Biology in molecular terms we get the right kind of explanations and, surprisingly, a new natural law.

Which is all the pre-history I hope you’ll need for the following review of the book. I’m about half-way through the text of the book myself and it seems like an admirable attempt to solve what is, in truth, a very sticky problem in the Philosophy of Science. If he can solve it then I might have to rethink my forthcoming article in ‘The Skeptic.’

John Dupré, in American Scientist, reviewing Alex Rosenberg’s ‘Darwinian Reductionism: Or, How to Stop Worrying and Love Molecular Biology,’ University of Chicago Press, 2006