Based on Aristotle's analysis of the form and matter found in human thought, this book examines the three steps the mind takes in arriving at the truth: defining, judging, and reasoning. The author further analyzes the type of material demanded for scientific or demonstrative knowledge: universal, necessary, and proper propositions and applies this examination to modern science.

This book will remain timeless in its study of Aristotle's objective grasp of reality. The book's uniqueness lies in its aim of letting Aquinas himself speak on the subject of metaphysics. The work embraces both a history of philosophy and Aristotle's subsequent reasoning toward God as pure act.

This volume is devoted St. Thomas's commentary on the Physics. In the Physics, Aristotle delves into what makes things what they are. In commenting on this fundamental text of Aristotelian philosophy, St. Thomas takes Aristotle's thoughts and deepens them.