According to Jean Piaget, knowledge or any form of learning should be acquired through assimilation and accommodation, such that the knowledge becomes a part of your own knowledge.

In psychology and sociology, internalization is the process of acceptance of a set of norms established by people or groups which are influential to the individual. The process starts with learning what the norms are, and then the individual goes through a process of understanding why they are of value or why they make sense, until finally they accept the norm as their own viewpoint.

Role models can also help. If someone we respect is seen to endorse a particular set of norms, we are more likely to internalize those norms. This is called identification. In Freudian psychology, internalization is one of the concepts of the psychological process of introjection, a psychological defense mechanism.

In developmental psychology, internalization is the process through which social interactions become part of the child’s mental functions, i.e., after having experienced an interaction with another person the child subsequently experiences the same interaction within him/herself and makes it a part of his/her understanding of interactions with others in general. As the child experiences similar interactions over and over again, s/he slowly learns to understand and think about them on higher, abstract levels. Lev Vygotsky suggested that mental functions, such as concepts, language, voluntary attention and memory are cultural tools acquired through social interactions.
http://en.wikipedia.org/wiki/Internalization