The first six chapters require no special preparation beyond a familiarity with advanced calculus. Chapter 1 features a survey of the prerequisite concepts and results, which may be consulted as needed. Subsequent chapters demand greater mathematical maturity, drawing from the fields of modern real analysis, theory of differential equations, functional analysis, and topology. However, the book is sufficiently self-contained that those without such a background can still master much of the second half. Ideal as a primary or supplementary text, this volume imparts fundamental knowledge of a field with widespread, profound implications while challenging readers to develop greater insights.