Reasons and biological causes. Some reflections on Boudon’s Theory of Ordinary Rationality

In his effort to provide sociology with a theory of behavior for the microfoundation of social phenomena, Raymond Boudon searched for a theory that could be presented as general (i.e., a theory that, given its strength, can be used “by default” in explanations). In this search, Boudon disregarded biological causes and stated that his Theory of Ordinary Rationality was the best choice, since it offers final explanations: when a behavior is explained as a result of beliefs that are grounded on good reasons, we are offering a black-box-free explanation. In this paper, I shall state that there are serious problems in the arguments that Boudon used to dismiss the explanatory strategy based on “biological causes”. Secondly, I shall point out that some recent findings of several behavioral sciences constitute a radical questioning of the value of his Theory of Ordinary Rationality, as well as a positive revaluation of Evolutionary Psychology. In light of these findings, we can state that on many occasions, either reasons are systematically biased by biological causes, or these causes cause behavior, thus reasons are mere rationalizations. Therefore, neither the reason-based explanatory strategy nor the biological causes-based explanatory strategy can be used “by default”. Given the current state of our knowledge, Evolutionary Psychology cannot stand as a general theory of behavior but is better placed to do the job in the future: it will depend on its ability to build models that integrate reasons and biological causes.