Human beings are agents: They may exert influence over their own fate.
They initiate their actions, experience a considerable degree of freedom
and control in their mundane activities, and respond adversely to
external constraints to their agency; they are able to monitor and
modify their moti- vation, affective states, and behavior. Since the
sixties, the notion of person-as-agent has become increas- ingly
accepted in scientific psychology. Nowadays, personal control is a
standard topic in research on personality, motivation, and social
behavior. The most popular approach identifies personal control with a
feeling or judgment: To have control means to perceive the self as a
source of causa- tion. Within this perspective, such consciously
accessible contents like perceived freedom and self-determination,
feelings and expectations of control, or perceived self-efficacy and
competence emerge as natural tar- gets of research (see e.g., Alloy,
Clements, & Koenig, 1993; Bandura, 1977; OeCharms, 1968; Oeci & Ryan,
1985; Harvey, 1976; Rotter, 1966; Thomp- son, 1993; Wortman, 1975).