Richard Feynman spends seven lectures at Cornell trying to answer one question: what does it mean for the universe to obey a law at all? Delivered in 1964 as part of the Messenger Lectures series and later published by the BBC as a book of the same name, the talks move from gravitation as a case study in what a physical law looks like, through the relationship between mathematics and physics, into the great conservation principles and the symmetries hidden inside them. Feynman works at a blackboard with chalk and diagrams, no props beyond his own hands and voice, building arguments about why past and future look different to us and why probability, not certainty, turns out to run quantum mechanics. The final lecture turns the camera on the process itself, Feynman describing how physicists go about guessing new laws and testing them against nature. The lectures are dense but plainly spoken, and the appeal is watching one of the field's clearest thinkers work through ideas in real time rather than summarize them.