Rationality and Logic

Abstract

It seems that more and more people are behaving unreasonably: they hold opinions for which there is no reasonable justification; they are easily persuaded by nonsense and scorn the role of institutions that were established in modern societies precisely to convey real knowledge to us. This is currently causing increased interest among experts in logic, critical thinking, and argumentation theory, because these disciplines promise to provide us with tools for explicitly distinguishing reasonableness from unreasonableness. Unfortunately, these approaches often work with a concept of reason that is too simplified and can thus do injury to rationality. Therefore, in this text I want to address the question of whether logic (or something else) can provide us with some simple measure of rationality. I come to the conclusion that it cannot, that neither rationality (reasonableness) nor logic are simple concepts, and judging whether someone is behaving rationally can be a very complex problem.