Toward an integration of economic and sociological approaches?

This article answers the question whether sociology of law and law and economics can be unificd into one integrated science. First, it is argued that an integration process inside law and economics has taken place, integrating most schools and partial analyses into one mainstream law and economics. Second, it is argued that there are no natural barriers against an integration of sociology and economics. Purely economic theories cannot and do not exist. What is called economic analysis of law is basically a mixture of, for instance, 70 percent economics, 10 percent sociology, 10 percent psychology, and 10 percent other sciences. In addition, there is no such a thing as a purely sociological concept; concepts are sociological only in the sense that they are invented by people who call themselves sociologists. Nevertheless one should not expect that such a richer social science will lead to fundamentally different predictions and policy recommendations than those derived from the current simplistic economic analysis of law. The aspects studied by sociologists but assumed away by legal economists to date have in most cases no influence on the determination of (optimal) legal rules or on the long-run effects of legal rules.