In 2016, the scuba-diving philosopher Peter Godfrey-Smith wrote Other Minds where he explored the mind of the octopus – I reviewed it right before reading this book. Its bestseller status, including translations in more than 20 languages, was not entirely unpredictable. Octopuses are a sexy topic. Four years later, he explores animal minds further with Metazoa, with the tour now also including sponges, corals, shrimp, insects, fish, and mammals. Godfrey-Smith convinced me he is no one-trick pony when it comes to writing a good book, though this one is more cerebral than its predecessor.