Immanuel Kant"s analysis of the knowledge process puts him in the forefront of the world"s greatest philosophers. The new book Kant is a fascinating biography of this eighteenth-century German, whose beliefs were far ahead of his time. Kant greatly influenced German idealism in the succeeding generation. When Albert Einstein was fifteen, his father handed him a copy of Kant"s The Critique of Pure Reason, and asked him to read it carefully. Throughout his life, Einstein tried to isolate the a priori factors underlying physical manifestation. His idea of subjective space-time is obviously derived from Kant. Neither Buddha nor Plato attempted anything like Kant"s endeavors. Kant asked these preliminary questions: What is it I know? How do I know it? How reliable is sensation or thought? What is the nature of the subject? Who am I? Is the mind a blank sheet in which experience writes whatever it wishes? Kant believed that sensation is possible only within two a priori forms of intuition:...