Editing Modern synthesis (20th century) (section)

==An obstruction: Woodger's positivism, 1929==

{{further|Joseph Henry Woodger}}

The [[theoretical biology|theoretical biologist]] and [[philosophy of biology|philosopher of biology]] [[Joseph Henry Woodger]] led the introduction of [[logical positivism|positivism]] into biology with his 1929 book ''Biological Principles''. He saw a mature [[science]] as being characterised by a framework of [[hypothesis|hypotheses]] that could be verified by facts established by [[experiment]]s. He criticised the traditional [[natural history]] style of [[biology]], including the study of [[evolution]], as immature science, since it relied on [[narrative]].<ref name=Smocovitis100>{{harvnb|Smocovitis|1996|pp=100–114}}</ref> Woodger set out to play the role of [[Robert Boyle]]'s 1661 ''[[Sceptical Chymist]]'', intending to convert the subject of biology into a formal, unified science, and ultimately, following the [[Vienna Circle]] of logical positivists like [[Otto Neurath]] and [[Rudolf Carnap]], [[reductionism|to reduce]] biology to physics and chemistry. His efforts stimulated the biologist [[J. B. S. Haldane]] to push for the axiomatisation of biology, and by influencing thinkers such as Huxley, helped to bring about the modern synthesis.<ref name=Smocovitis100/> The positivist climate made natural history unfashionable, and in America, research and university-level teaching on evolution declined almost to nothing by the late 1930s. The Harvard physiologist [[William John Crozier]] told his students that evolution was not even a science: "You can't experiment with two million years!"<ref name=Smocovitis114>{{harvnb|Smocovitis|1996|pp=114–119}}</ref>

The tide of opinion turned with the adoption of [[mathematical model]]ling and [[controlled experiment]]ation in population genetics, combining genetics, [[ecology]] and evolution in a framework acceptable to positivism.<ref name=Smocovitis119>{{harvnb|Smocovitis|1996|pp=119–122}}</ref>