What term describes the phenomenon when individuals conform to group beliefs that they truly agree with?

The term that describes the phenomenon when individuals conform to group beliefs that they truly agree with is internalisation. Internalisation occurs when a person's private beliefs align with the views of a group, leading them to adopt those beliefs as their own. This often results in lasting changes in attitudes, even in the absence of the group, because the individual genuinely believes in the ideas they have adopted.

In contrast, identification involves adopting the beliefs or behaviors of a group to establish or maintain a relationship with them, but the individual may not fully agree with these beliefs. Compliance refers to yielding to group pressures even when there is private disagreement, often in order to avoid conflict or gain approval. Social facilitation is a different concept that describes how the presence of others can improve performance on tasks, not specifically related to belief conformity. Therefore, internalisation is the most precise term to describe the situation where individuals adhere to group beliefs because they genuinely agree with them.