Although there are many references to the phatic function of language in linguistic and anthropological literature, little is said about its underlying causes. In this article, which is predominantly an analytical study, through combining relevant facts, a hypothesis is put forward that the phatic function of language is based on a number of psychophysiological reasons. In order to clarify them, we have studied a number of psychological (a model developed by the transactional method of Eric Berne) and biological phenomena (facts from observations of the behavior of primates carried out by Robin Dunbar), which we have compared with the results of a survey conducted at Brusov State University. We have come to the conclusion that many statements often used during everyday conversation are based both on the instinct of self preservation, and, therefore, on the desire to be in a certain group, and on physiological changes (in particular, an increase in the number of endorphins) that occur between interlocutors when they convey verbal caresses to each other.