Life's Ratchet

Peter M. Hoffmann

Why I looked at this book

In the macroworld we are used to machines that obey straightforward rules - we issue a command and something happens. In the microworld things are more complex - stuff happens according to the rules of thermodynamics. So if say a hormone has a task to do, a large dose of randomness will be involved in getting it done. I'm hoping that this book will help me to get my head around this puzzle.

First impressions

The sample is short, but it certainly looks to be heading in the direction I was hoping for, asking 'How does chaos become life', and looking at what has been thought about this question by early philosophers.

Main review

After a chapter looking at historical ideas of what life is, the book spends quite a while on discussing the nature of chance, thermodynamics and entropic forces, getting on to a chapter on Maxwell's demon and Feynman's ratchet. This gives a gentle introduction to the reader unfamiliar with the concepts involved, but it has also has plenty of interest to more knowledgable readers. The book then gets on to the workings of life at the small scale, including enzymes. In particular it looks at proteins that can walk along a structure, and discusses the difference between tight and loose coupling - different ways of getting a definite motion when your main resource appears largely random. Overall, I would say that the book succeeds in dealing with the role of randomness in the workings of life, and in introducing the reader to what's going on within our cells in a non-technical way. I'd recommend it to anyone wanting to get a better idea of how life works at the level of molecules.

Reviews Elsewhere

Amazon Reviews and Goodreads Reviews are positive. One reviewer suggests the paper The Algorithmic Origins of Life gives a better treatment of the subject, and some think that the author fails to distinguish Shannon Information and functional information, but most think that it's excellent. See detailed reviews at The Finch and Pea and at The Panda's Thumb