On 25th October 1946, in a crowded room in Cambridge, Ludwig Wittgenstein and Karl Popper came face to face for the first and only time. The meeting was a disaster, their loud and aggressive confrontation became the stuff of legend. This book tells what really went on in that room.

“It’s not good enough to say there’s some mechanism such that you start out with amoebas and you end up with us. Everybody agrees with that. The question is in this case in the mechanical details. What you need is an account, as it were step by step, about what the constraints are, what the environmental variables are, and Darwin doesn’t give you that.”.