Efficiently Irrational: Illuminating the Riddle of Human Choice

For the past half century cognitive and social scientists have struggled with the irrationalities of human choice behavior; people consistently make choices that are logically inconsistent. Is human choice behavior evolutionarily adaptive or is it an inefficient patchwork of competing mechanisms? This review presents an interdisciplinary synthesis arguing for a novel interpretation; choice is efficiently irrational. Connecting findings across disciplines suggests that observed choice behavior reflects a precise optimization of the trade-off between the costs of increasing the choice mechanism’s precision and the declining benefits that come as precision increases. Under these constraints a rationally imprecise strategy emerges which works towards optimal efficiency, rather than towards optimal rationality. This approach rationalizes many of the puzzling inconsistencies of human choice behavior, explaining why these inconsistencies arise as an optimizing solution in biological choosers.