Aristotle - the master of those who know. For fifteen hundred years he remained the paradigm of knowledge itself, a foundational thinker in every field of inquiry. Aristotle established a systematic logic, conceived the earliest science, a rational psychology, a political science and an outline of sociology, and gave us a crucial theory of ethics. His contributions to metaphysics continue to permeate modern philosophy. He supplied the first theory of aesthetics, and investigated dialectics and semiotics - essential to debates in postmodernism. Scientific empiricism in the 17th century, however, is said to have discredited his methods. How scientific is Aristotle?