The origin of consciousness was a world-defining event, comparable only with the origin of life itself. But the moment that consciousness emerged is buried deep in the evolutionary record and is hard to identify.

In this article, Simona Ginsburg and Eva Jablonka put forward their new theory about how and when consciousness evolved. They identify a unique marker of minimal consciousness that they believe drove the Cambrian explosion of biodiversity and answers the age-old question of which organisms are conscious.

MuZero is an algorithm with a superhuman ability to learn: it has learned to play 57 different Atari video games as well as Chess, Go and Shogi, and defeated the greatest human masters in every one of them. Yet, this amazing algorithm and the computer in which it is implemented are as conscious as your washing machine. Its “intelligence”, manifest in its learning ability, has nothing to do with consciousness – the ability to feel, perceive and think in the deeply subjective sense that we cherish. If you were told that you would become deprived of all subjective perceptions and feelings, you would be devastated and consider such a life to be meaningless. Intelligence – having the ability to learn and solve complex problems like MuZero does –  and consciousness – being the subject of experience – seem to be unrelated.