Introduction

Over the last few years, economics has experienced significant changes. These have concerned both new substantive subjects of research and new theories, methodologies and analytical tools. As regards subjects, the interest of economists has been increasingly attracted by matters — such as intrinsic adherence to social norms, other-regarding preferences and non-instrumental reciprocity — previously considered to be ‘non-economic’ phenomena (and the exclusive competence of other disciplines: psychology and sociology, and perhaps moral philosophy). As regards theories, methodologies and tools, new approaches characterized by high interdisciplinarity — such as behavioral economics and behavioral law and economics, experimental economics, ‘psychological’ games, and more generally behavioral game theory — have been developed and have spread throughout the economics profession. Substance, theory, methods and tools are closely interwoven because new approaches have been developed and/or applied in the analysis of new topics (for example, the experimental approach has been widely used to explain the extensive evidence of deviations from the behavior predicted on the basis of standard microeconomic models; deviations associated with what we may intuitively call social reciprocity, conformity with norms, not strictly selfish behavior, trust and trustworthiness, etc.).