Annals of the History and Philosophy of Biology

Was there a Darwinian Revolution?
So, no Darwinian Revolution in this sense. But I still go back to the point I made earlier.
I am just not prepared to take the present out of the picture. Darwin did get it right
about selection! It took seventy-five years for this to become apparent, but then it did
and it has stayed that way. So, if you are prepared to use the present as a guide to the
past – and I have defended this practice – so long as you do not gloss over how history
took time to develop, I see no reason to deny Darwin’s role in the Darwinian Revolution.
And much good reason to think that the revolution is appropriately named.
Was there a Darwinian Revolution?
Here my question is about the nature of the revolution, meaning more about what kind
of revolution it really was. In other words, my question is more of a philosopher’s question,
trying to understand the nature of science and the way in which it changes. The
name and work of Thomas Kuhn lurks large. So let us phrase the question in Kuhnian
terms: Was there a change of paradigms in the sense described by Thomas Kuhn in his
The Structure of Scientific Revolutions? Was there a switch of world views – perhaps even a
switch of worlds – that required more of a leap of faith than an appeal to reason? Or was
the change smoother, as more conventional philosophies of science might lead one to
expect. Was the change more (say) in a Popperian vein, where basically the facts told
against the older position and people shifted because this was the reasonable thing to do?
After nearly forty years of looking at the revolution, my answer is an unequivocal –
yes and no (and maybe)! At a broad level, there are certainly Kuhnian aspects to the
revolution. Most strikingly, there were people who simply could not see the other side’s
point of view – clever people, that is, who knew the ins and outs of the issues. Most
prominent of these was the Swiss-American ichthyologist Louis Agassiz (E. C. Agassiz
1889). He had staked out an idealistic position before the Origin (Agassiz 1859) – one
that came directly from his Naturphilosophen teachers (Friedrich Schelling and Lorenz
Oken) when he was a student in Munich – and try as he might, he could never accept
evolution, even a Germanized form that was being pushed by people like Ernst Haeckel
(1866). To Agassiz’s credit, he really did try – his students around him, including his own
son, were becoming evolutionists in the 1860s -- but it was not for him.
Something like this makes perfect sense on the Kuhnian scenario and, in my opinion,
fits uncomfortably into the Popperian (1959) scenario – although in fairness to the memory
of Popper, I should add that he himself thought that the Darwinian Revolution
was more metaphysical than purely science and so probably would not think Louis Agassiz
a refutation of his position (1974). So let me simply say, without trying to attribute
positions to people, that Agassiz does not fit comfortably into a philosophy of science
that makes rational choice the sole criterion of theory change.
However, in other respects the Darwinian Revolution seems clearly very non-
Kuhnian. There have been major arguments about what precisely Kuhn meant by “different
worlds” – my own inclination is to say, on rereading the first edition of The Structure
of Scientific Revolutions, that Kuhn meant a real ontological change, although tempered
by the fact that ontology (in a kind of Kantian sense) has to be mediated through the
Annals of the History and Philosophy of Biology, Vol. 10 (2005)
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