Locus of control, though, is of particular interest as we explore mastery. The concept was developed by psychologist Julian B. Rotter to describe the degree to which people think they can control the outcomes of events in their lives. People with an internal locus of control believe that they have a high degree of influence over what happens to them. People with an external locus of control believe the opposite, that fate and other people shape their lives.
Maybe a more commonly used term for what I've talked of as agency
