Change is the Only Constant: The Wisdom of Calculus in a Madcap World

Ben Orlin examines the mathematical study of change through two core lenses: the derivative and the integral. Using hand-drawn sketches and comedic analogies, the text connects geometric slopes and areas to a variety of practical and historical scenarios. Orlin discusses Archimedes’ exhaustion method, the rivalry between Newton and Leibniz, and how differential equations model shifting population sizes. Each chapter highlights a specific application, such as the physics of a falling object, the logic of financial markets, or the way Sherlock Holmes applies deductive change to solve a mystery.

This book serves students who feel intimidated by formal notation and curious adults who want to understand the logic behind the formulas they memorized in school. Readers walk away with a conceptual grasp of how instantaneous rates of change and accumulation function in the natural world. By removing the dense jargon typical of textbooks, Orlin provides a mental map for identifying calculus in daily life, from the trajectory of a ball to the long-term patterns of human behavior.