Energy, Entropy, and the Flow of Nature presents the essential principles of energetics (thermodynamics) in a straight-forward, easy to understand, and logically-consistent manner. As a student of physical chemistry and as a professor and researcher in biochemistry, physiology, and general biology, the author has seen the problems that arise for students, teachers, and researchers in mastering the laws of thermodynamics. These difficulties can be alleviated by a careful consideration of the historical roots of the ideas involved, and by recognizing that all natural change can be understood as a flow across a gradient of some kind. Part of the effect of every flow is to diminish its own gradient, but the decrease of one gradient can drive an increase in another. The book's mission is to build a solid understanding of the fundamental concepts of energetics and a confidence in going forth into the many areas that the study of energy opens up. In their applications, the laws of energy and entropy can often involve highly challenging problems and calculations, but the fundamental concepts addressed in this book are easy to understand and require relatively little mathematics.