Abstract
From a cognitive point of view, the adhesion to religious beliefs, especially those involving adult subjects, are quite mysterious. Religious representations entail paradoxical claims that should imply skepticism or cautious doubts in any rational mind. Nevertheless, it is not rare that they prompt an act of total commitment from the converts. The aim of this paper is to propose a naturalist explanation of the conversion phenomenon. The argument relies on the postulated existence of an emotional signal selected by evolution to motivate the child to look for the underlying structure of the world by providing a strong positive feeling when a solution is found. By the use of different examples of historical conversions, the author shows how this emotional mechanism can be triggered in the presence of religious representations, causing in the subjects the feeling that they have discovered a good solution to problems they were confronted with.