How scientific studies of human behavior can be replicated with the consistency and rigor characteristic of the physical sciences, yielding scientific “laws.” In Laws of Human Behavior , Donald Pfaff and Sandra Sherman argue that many behavioral and neural discoveries—verified over the years through precise, reliable measurement—are tantamount to “laws,” comparable in rigor and replicability to physical laws such as gravity and the second law of thermodynamics. Drawing on research in areas including psychophysics, various types of conditioning and habit formation, and even social behaviors, they show how important aspects of the behavioral sciences contribute to laws that should be celebrated now. Responding to what some commentators have called a crisis in reliability, the authors make a compelling case for the progress that experimental work in areas, formerly labeled as “soft” science, has achieved. The book is international in scope. References range from the early nineteenth-century work of Weber to papers published in 2023. In particular, the authors cite important accomplishments in the behavioral and neural sciences of the past few decades that support the characterization of these sciences as “exact.” Each chapter of the book has three parts: examples of the law’s manifestations in everyday life, examples of the laboratory science that supports the law, and neurobiological results that further support the validity of the law. The book also offers clues for understanding where the field of behavioral science is headed.  The authors intend for the book to be accessible to interested nonscientists.