Let us get through the tough and abstract part of saying why social roles are the fundamental unit of social life before getting on to some clear cut examples of social roles. A social role is any human activity that can be named, which is the same thing as to say that it is any human activity that can be typified, which means that it can serve as a model for such behavior, people comparing how they carry out an activity with the idea of the activity. Men and women are two different social roles, even if there are some cases that make this other than a binary choice, and even though it is a presumption to guess at some fundamental psychological makeup for these two (or more) roles rather than to settle for a definition of the two in terms of their overt biological characteristics.

A social role can be defined by its function or its circumstances or some combination of the two. Occupational roles usually center on functions. The job of a janitor is to clean up the floors so that other employees can use the offices, though it is also the case that janitors work at night when the rest of the employees are not there, and so share much in common with other night shift workers, like bakers, a lack of supervision and a family life that doesn’t follow the usual nine to five routine. Customary roles focus on circumstances. A priest may be someone who officiates at a liturgy, that being the essential function of a priesthood, even if it also provides other services to congregants, such as advice or consolation, but the main thing about a Catholic priest is a circumstance, his celibacy, which has for a thousand years been used as a sign of his elevation from his parishioners. Marriage is also mainly a set of circumstances: a shared bed and legal obligations one to another, whatever the state of affection between the two parties.