René Descartes, considered the founder of modern philosophy, also played an important role in what is now called the scientific revolution, which inaugurated the modern conception of scientific knowledge. He elaborated a comprehensive philosophical system spanning metaphysics, physics, physiology, and ethics. Like Francis Bacon and Galileo, Descartes developed his system in conscious opposition to the dominant scholastic philosophy of the time, a Christianized Aristotelianism as interpreted by Thomas Aquinas and other late-medieval thinkers. Descartes's own philosophy was founded in what he considered to be evident truths intuited by the natural faculty of reason. His metaphysics centered on the establishment of the individual subject, a being characterized by rational thought. He considered the mind of this subject as completely distinct from all matter, including the body, although the mind and body are connected and can affect each other. This theory is the famous Cartesian "mind-body split," although the...