Philosophy of biology versus philosophy of physics.

Not long ago I witnessed a remarkable interchange between two great thinkers: the cosmologist and physicist John Archibald Wheeler, and the philosopher of science Sir Karl Popper. Popper and Wheeler were meeting with a dozen other philosophers and scientists at Schloss Kronberg, the Victorian castle built by Kaiser Wilhelm's mother outside of Frankfurt during the closing years of the nineteenth century. The group was gathered in the late afternoon around an enormous round table in the Grand Salon, and Wheeler had just delivered a brilliant exposition of his own interpretation of quantum mechanics. Popper turned to him and quietly said: "What you say is contradicted by biology ". It was a dramatic moment A hush fell around the table. The physicists present appeared to be taken aback. And then the biologists, including Sir Peter Medawar, the Nobel prizewinner who was chairing the meeting, broke into a delighted applause. It was as if someone had finally said what they had all been thinking2. No one present meant to suggest that the reported facts of physics and biology were in conflict - nor even that physical and biological theoiy were in conflict. Rather, it was meant that fhe interpretation (or philosophy) of physics was incompatible with fact and interpretation in the life sciences. Behind Popper's remark, unstated on this occasion yetlending it bite, was yet another contention: that the interpretation of physics that had been presented did not apply to physics either. Philosophy of science in the twentieth century has been dominated both by physics and by a particular interpretation of physics. This interpretation - having to do with the subject matter and purpose, the scope and limitations, the justification and degree of certainty, of the sciences - is rooted in eighteenth-century British empiricism, in the thought of Bishop Ber