Freeman Dyson - The origins of life (141/157)

To listen to more of Freeman Dyson’s stories, go to the playlist:    • Freeman Dyson (Scientist)  

Freeman Dyson (1923-2020), who was born in England, moved to Cornell University after graduating from Cambridge University with a BA in Mathematics. He subsequently became a professor and worked on nuclear reactors, solid state physics, ferromagnetism, astrophysics and biology. He published several books and, among other honours, was awarded the Heineman Prize and the Royal Society's Hughes Medal. [Listener: Sam Schweber; date recorded: 1998]

TRANSCRIPT: I have always been interested in biology and clearly the central problem of biology in a certain way is the origin of life, how did it all get started. And, so I read Oparin's little book and various others; I think Haldane wrote a little book about origin of life and Purnell [sic] I think... anyway there's a standard literature about this. And then I was in La Jolla doing Orion, next door was the Salk Institute where Leslie Orgel was. Leslie Orgel is a chemist who's done real experiments on DNA and other essential components of life, and he was... has always been interested in this question of origins. So actually, I was there for a year and we had many meetings and conversations which we would go over this question of how the whole thing could begin, and it was clear that there was a kind of a paradox. That the... life has to be able to replicate; that's sort of the definition of life according to the orthodox view, which means you have to have exact copying of molecules, and how can a replication system then ever get established? It has to be able to replicate itself and somehow or other it has to lift itself up by its bootstraps from a thoroughly disorganised state, which is the sort of natural chaos from which things originate, into something that's highly organised, able to replicate. And the problem is that on the way up, you have a system which is bad but still partly replicating which has a high error rate, so it can replicate itself with a lot of errors before it's become a good replicator. But if you do the arithmetic you find out that it'll slide down again, that the errors multiply as... as the generations go by. So that if you have something that's 90% accurate and then it tries to replicate, in the next generation you'll get the same 10% errors, plus a few more because of the fact that the system is not perfect. So the next generation is worse than the one you're in. So the mathematics is always against you. It seems very, very difficult to get a replicating system to jump from disorder to order. So were sort of stymied, Orgel and I, and it's remained like that ever since. The orthodox view among biologists is that life has to start with replication and it then becomes very, very hard to get over this very first step; how can it overcome this error, what we call the error catastrophe, the fact that errors propagate more rapidly than the... the amount of information? So I finally decided one has to make a completely fresh start and have life without replication, which to my mind is not such a great difficulty. I mean of course it goes against all the prevailing dogmas of the biologist. The idea is that you could have a replicating system coming in much later, when life already existed, and then it becomes a much easier problem. But how could life even start without replication? Well, that then is the question that I addressed and I think I made some progress with that.