‘Analogia’ is an unconventional book which takes the reader on a centuries-long journey of the evolution of technology from analogue to digital and (sort of) back again. Analogia: The Entangled Destinities of Nature, Human Beings, and Machines (Allen Lane, £25, ISBN: 9781846147449) is an odd book. Author and historian of technology George Dyson weaves together autobiography, science and 300 years of history into a sprawling exploration of how technology, nature and humanity have shaped each other and will shape each other in years to come. Dyson identifies four human “epochs” with distinct relationships between humans and machines: a pre-industrial epoch in which technology is limited to handmade tools; an industrial epoch in which machines made machines; a digital epoch in which digital codes make copies of themselves (self-replicating like organisms); and an epoch we are entering now, in which technology is arguably growing beyond our control and understanding. “In the fourth epoch, so gradually that almost no one noticed, machines began taking the side of nature and nature began taking the side of machines,” Dyson writes. “Humans were still in the loop, but no longer in control. Faced with a growing sense of this loss of agency, people began to blame ‘the algorithm’, or those who controlled ‘the algorithm’, failing to realise there was no longer any identifiable algorithm at the helm. The day of the algorithm was over. The future belonged to something else.” Dyson recounts the story of humans, technology and nature in a loving and leisurely manner, with enough lengthy digressions to make Victor Hugo say “steady on, mon pote”. Readers should expect to learn a lot about canoes along the way, whether they like it or not. Some of these digressions are fascinating and insightful; others teeter on the edge of self-indulgence. The most charming parts of ‘Analogia’ are Dyson’s own recollections of his childhood years at the Institute for Advanced Study: home to some of the greatest mathematicians and scientists of the twentieth century, including Einstein, von Neumann, Gödel, and Dyson’s own parents (the theoretical physicist Freeman Dyson and mathematician Verena Huber-Dyson). This tome may be worth reading just for this unique glance into the everyday lives of geniuses from the perspective of a young child growing up in their world. Dyson returns throughout ‘Analogia’ to the complex, shifting analogue and digital nature of humanity (e.g.: the nervous systems is analogue and DNA is discrete) and machines. In the fourth epoch, “the power of the continuum will be claimed by machines”, he claims. He concludes that machines are now evolving beyond our command and understanding, and the idea that AI can be programmed to do our bidding is as unfounded as the belief that some people can speak to gods or that others are born as slaves. “Nature’s answer to those who seek to control nature through programmable machines is to allow us to build systems whose nature is beyond programmable control.” While Dyson’s final conclusion is hardly ground-breaking, he deserves praise for so defiantly breaking out of conventional science and technology writing styles and formats. ‘Analogia’ is a winding, unexpected exploration of 300 years of humans, nature, and technology; this reviewer suspects that readers will be alternately enchanted and frustrated by its digressions.