Both of these disciplines are curious about human development of the self, but focuses more on internal influences while focuses more on external influences.

   Psychology; sociology

Explanation:  Psychology as a science that therefore deals with the human self, focuses on the internal processes of self development, therefore studies the human mind, as well as the consequent behaviour on the basis of the mind set. There are many theories and techniques developed here, such as psychoanalysis for the aforementioned studies, and the goal is to look at the internal mental processes and consequential behaviours that are present as such and are part of society and community. Of course, this science is important for the study of the human self as part of the general community, its influence, its changes due to social circumstances and environment, etc., but the emphasis is primarily on internal processes.

Sociology, on the other hand, deals with the external influences of society, its development, change, turmoil, and how they affect the said development of the human self. The environment is an important factor in the formation of the self, therefore external influences are at stake. In the environment, i.e in social relations, social relationships, interactions, cultures of everyday life are shaped, all of which affect the development of the self, of course.