ABSTRACT
Today, it seems commonplace to emphasise that behavioural modifications affect the functions of our internal organs and, vice versa, that visceral changes can modify behaviour. This statement—which may now appear to most of us as banal—has a long and controversial history which cannot be regarded as having been clarified. On the contrary, it hides a series of unresolved, open problems. In this paper, we try to approach some of them.
