Rationality was not embedded in economic theory from its onset. In fact, the discipline started with a more holistic approach to human nature, incorporating notions of empathy and altruism. It was not until economics progressed and became more concerned with mathematical models and abstract theories that rationality entered the fray. Game theory, developed in the 1940s, established several axioms about human behavior that presented people as perfectly rational economic agents. It was not until behavioral researchers started investigating the question of rationality that the economic worldview was critically challenged. This research was the driving force in the development of behavioral economics. In particular, ultimatum game experiments d...