The Origin of Life by A. G. Cairns-Smith — Summary, Key Ideas & Quotes

Cairns-Smith's central thesis is that life may have originated with clay crystals, not organic molecules. He argues that the regular, replicating patterns in certain clays could have provided a primitive form of 'genetic' information, much like DNA does today. These mineral structures could have acted as templates, accumulating and transmitting information through their patterns as they grew and broke apart. This idea radically departs from the 'primordial soup' model, suggesting that inorganic matter played a direct, active role in life's beginnings.

The book emphasizes that life's defining feature is not just its chemistry, but its ability to store and transmit information. Cairns-Smith points out that even the simplest living systems require complex instructions to reproduce themselves. He suggests that before organic evolution could get started, there had to be a system—possibly in crystals—that could accumulate, copy, and occasionally mutate information, paving the way for natural selection long before genes.