i would add to this that early conceptualizations of psychology have had massive cultural impacts. if you enjoy art, film, literature from the last century and change, it’s worth knowing about Freud and Jung.
their ideas represent an evolution of thinking about people, their minds, their relationships to others and to their environment or to god, but they also underpin so much we take for granted at present in popular culture and day-to-day conversation (at least in “the west”).