Living on Earth is the third volume in a trilogy that began with Other Minds in 2017 and continued with Metazoa in 2020. These books are not easy to classify. Part natural history, part theoretical science, part philosophy, they don’t fit neatly into any of the normal categories. But readers of the previous volumes will know what to expect. Peter Godfrey-Smith is both a leading
philosopher of biology and a committed observer of the natural world, especially the bit that lies beneath the sea (his publisher characterises him as a ‘scuba-diving philosopher’). He combines his talents to deliver a distinctive mix of theoretical insights and history of natural wonders.

Other Minds focused on octopuses. These are smart – they have more brainpower than the average dog – but they are also very strange, since they evolved from shelled animals like mussels or snails and as a result their brains are distributed all over their boneless bodies. Godfrey-Smith used them to explore the nature of intelligence, drawing on his first-hand diving experiences. As he saw it, an encounter with an octopus was as close as we could get to meeting an intelligent alien.

In Metazoa, Godfrey-Smith expanded his horizons to encompass all animal life and address the mystery of consciousness. Or rather, as a committed materialist, he sought to dissolve the mystery by showing us how evolution has produced a bewildering variety of organisms, each with its own way of relating to its