Economics Nobel Laureate Herbert Simon developed the concept of bounded rationality in the 1950s. This asserts that the cognitive abilities of human decision-makers are not always sufficient to find optimal solutions to complex real-life problems, leading decision-makers to find satisfactory, sub-optimal outcomes. This was a foundational component of the development of Behavioural Economics but in recent years the two fields have diverged, each with its own literature, its own approach and its own proponents. Behavioural Economics explores the areas of commonality between Economics and Psychology, in terms of its focus and its approach, whereas the bounded rationality literature largely analyses the implications of sub-optimal decision‐making through the mathematically sophisticated methodology of mainstream Economics. This book examines the nature and consequences of this divergence and questions whether this is a case of beneficial specialisation or whether it is unhelpful, potentially stunting the development of some aspects of Economics. It has been suggested that the major deficiency of Behavioural Economics is that it has failed to produce a single, widely applicable alternative to constrained optimisation. This book evaluates the extent to which this is the true and, if it is, the extent to which it is a product of the divergence between the two literatures. It also seeks to identify commonalities between the two subjects and suggests avenues of research in Economics that would benefit from a re-fusion of these two fields.

In a complex and uncertain world, humans and animals make decisions under the constraints of limited knowledge, resources, and time. Yet models of rational decision making in economics, cognitive science, biology, and other fields largely ignore these real constraints and instead assume agents with perfect information and unlimited time. About forty years ago, Herbert Simon challenged this view with his notion of "bounded rationality." Today, bounded rationality has become a fashionable term used for disparate views of reasoning. This book promotes bounded rationality as the key to understanding how real people make decisions. Using the concept of an "adaptive toolbox," a repertoire of fast and frugal rules for decision making under uncertainty, it attempts to impose more order and coherence on the idea of bounded rationality. The contributors view bounded rationality neither as optimization under constraints nor as the study of people's reasoning fallacies. The strategies in the adaptive toolbox dispense with optimization and, for the most part, with calculations of probabilities and utilities. The book extends the concept of bounded rationality from cognitive tools to emotions; it analyzes social norms, imitation, and other cultural tools as rational strategies; and it shows how smart heuristics can exploit the structure of environments.

Offering alternative models based on such concepts as satisficing(acceptance of viable choices that may not be the undiscoverableoptimum) and bounded rationality (the limited extent to which rationalcalculation can direct human behavior), Simon shows concretely whymore empirical research based on experiments and direct observation, rather than just statistical analysis of economic aggregates, isneeded.

Two leaders in the field explore the foundations of bounded rationality and its effects on choices by individuals, firms, and the government. Bounded rationality recognizes that human behavior departs from the perfect rationality assumed by neoclassical economics. In this book, Sanjit Dhami and Cass R. Sunstein explore the foundations of bounded rationality and consider the implications of this approach for public policy and law, in particular for questions about choice, welfare, and freedom. The authors, both recognized as experts in the field, cover a wide range of empirical findings and assess theoretical work that attempts to explain those findings. Their presentation is comprehensive, coherent, and lucid, with even the most technical material explained accessibly. They not only offer observations and commentary on the existing literature but also explore new insights, ideas, and connections. After examining the traditional neoclassical framework, which they refer to as the Bayesian rationality approach (BRA), and its empirical issues, Dhami and Sunstein offer a detailed account of bounded rationality and how it can be incorporated into the social and behavioral sciences. They also discuss a set of models of heuristics-based choice and the philosophical foundations of behavioral economics. Finally, they examine libertarian paternalism and its strategies of “nudges.”

Ît then rigorously analyses each model in the tradition of microeconomic theory, leading to a richer, more realistic picture of consumer behavior. Ran Spiegler analyses phenomena such as exploitative price plans in the credit market, complexity of financial products and other obfuscation practices, consumer antagonism to unexpected price increases, and the role of default options in consumer decision making. Spiegler unifies the relevant literature into three main strands: limited ability to anticipate and control future choices, limited ability to understand complex market environments, and sensitivity to reference points. Although the challenge of enriching the psychology of decision makers in economic models has been at the frontier of theoretical research in the last decade, there has been no graduate-level, theory-oriented textbook to cover developments in the last 10-15 years.

Herbert Simon’s renowned theory of bounded rationality is principally interested in cognitive constraints and environmental factors and influences which prevent people from thinking or behaving according to formal rationality. Simon’s theory has been expanded in numerous directions and taken up by various disciplines with an interest in how humans think and behave. This includes philosophy, psychology, neurocognitive sciences, economics, political science, sociology, management, and organization studies. The Routledge Handbook of Bounded Rationality draws together an international team of leading experts to survey the recent literature and the latest developments in these related fields. The chapters feature entries on key behavioural phenomena, including reasoning, judgement, decision making, uncertainty, risk, heuristics and biases, and fast and frugal heuristics. The text also examines current ideas such as fast and slow thinking, nudge, ecological rationality, evolutionary psychology, embodied cognition, and neurophilosophy. Overall, the volume serves to provide the most complete state-of-the-art collection on bounded rationality available. This book is essential reading for students and scholars of economics, psychology, neurocognitive sciences, political sciences, and philosophy.

This is an excerpt from the 4-volume dictionary of economics, a reference book which aims to define the subject of economics today. 1300 subject entries in the complete work cover the broad themes of economic theory. This extract concentrates on utility and probability.