Of course during this period every one of one's colleagues has always said that the book that influenced them most is What Is Life. A little book written by Erwin Schrödinger, which... you know, which people say: 'Were it not for Schrödinger, I would be playing the violin and collecting money on a… in an underground station in... in the tube'. And I actually read this book myself and in fact I have a copy here which you can see was bought in 1944, so I'd read this at a very early stage and I must say that I don't recall getting anything out of it in terms of what other people claim to have got, namely that it introduced them to the concept of the gene as a molecule and so on. I remember reading it as, as very interesting, of course I knew all about genes and chromosomes and this stuff seemed to me to be a bit amateur. I didn't understand the... the entropy part of the argument but in fact I have an inscription in my book which is a quotation from Faraday and, which said… says something and must be my... my impression of it at the time, and it says here, 'Let the imagination go, guarding it by judgement and principle, but holding it in and directing it by experiment'. So that is just the evidence it says… well, it's a great story but you know where are the experiments to tell you that it's true? And I think that that – which is written there, at the time – just says what… what this influenced me, and I think it's been very important, at least in my approach, which is that you've got to really find out. The difference between having a correct theory and a true theory… that is, a theory which reflects reality – you've got to go and actually go back to nature, and that's what this is saying.