Ever wonder why you don't walk into walls? How you know you have to step gingerly on ice? How you decide whether you can or can't scale a certain rock? My guest today says the answer lies in our special sense of bodily know-how. His name is Scott Grafton, and he's a neurologist and the author of Physical Intelligence: The Science of How the Body and the Mind Guide Each Other Through Life. We begin our conversation discussing how physical intelligence is the mutually responsive interaction between your body and your mind that allows you to interact effectively in the world. Scott then explains how our mind and body work together to build our conception of space and that without this ability we couldn't create an area of operations in which to take action. We then discuss how our mind and body communicate with various types of terrain, how we can lose that ability by limiting our movements to simple, safe environments, and how that may explain why old people fall down more. We then discuss how problem-solving can be a very physical activity and whether the feeling of fatigue is more a matter of the body or the mind. We end our conversation discussing ways you can keep your physical intelligence sharp as you age. Get the show notes at aom.is/physicalintelligence.