Immanuel Kant taught and wrote prolifically about physical geography yet never traveled further than forty miles from his home in Kvnigsberg. How appropriate it is then that in his philosophy he should deny that all knowledge was derived from experience. Kant's aim was to restore metaphysics. He insisted that all experience must conform to knowledge. According to Kant, space and time are subjective; along with various "categories," they help us to see the phenomena of the world-though never its true reality. In Kant in 90 Minutes, Paul Strathern offers a concise, expert account of Kant's life and ideas and explains their influence on man's struggle to understand his existence in the world.