The subject of psychology clearly includes the study of social relations and how they become internalized in the mind.
I'm going to be terse here because I could quickly get out of my depth.
What _is_ "The Subject" of psychology? What does it study.
We can presume that the brain, at a deep level, operates the same in
different contexts. (Or can we?) But is there such a thing as "the mind"
in abstracton from the social relaitions in which the personis enmeshed?