The Strategic Use of Fidelity in Romantic Relationships

This book offers a bold reinterpretation of monogamy, framing it not as a reflection of romantic desire but as a calculated effort to secure exclusivity from a partner. Despite widespread dissatisfaction, infidelity, and high divorce rates, monogamy remains the dominant relationship model. Rather than attributing this persistence to irrationality or tradition, James K. Beggan explores monogamy as a defensive practice—a strategic agreement in which individuals seek commitment primarily to ensure their partner’s fidelity. Rooted in fear of loss, jealousy, and emotional insecurity, this book reveals how monogamy often functions as a protective mechanism rather than a mutual aspiration. People overestimate their ability—or willingness—to uphold monogamous commitments, viewing them less as personal convictions and more as tools for managing risk. Drawing on interdisciplinary research across behavioral economics, psychology, sociology, and decision science, this book reconceptualizes monogamy as a form of social bargaining. By shifting the focus from morality to strategy, it challenges the ideal of romantic exclusivity and raises a provocative question: Are declarations of loyalty expressions of love, or are they evidence of doubt dressed as devotion?