Among distinguished sociologists, George Herbert Mead, through his lectures, came to have a profound effect on the development of symbolic interactionism. His lecture notes were posthumously published in a number of major volumes - Mind, Self and Society, The Philosophy of the Act and The Philosophy of the Present.
In Mead's philosophy, the self emerges through the process of social interaction with others. In his social behaviourism, the conditioned responses of human beings include gesture and role-taking, which are the bases of social life.
Gestures and conversation are crucial features of the symbolic interaction, the distinctive feature of which is that the individual can imagine the effect of symbolic communication on other social actors.
Human actors carry on an 'internal conversation' with the self and and anticipate the response of other actors. We imaginatively assume other social roles and internalize the attitudes of the generalized other - the attitudes of the social group.