In psychology, agency signifies the concept of a person's ability to initiate and control their actions, and the feeling they have of being in charge of their actions. The topic of agency can be divided into two topical domains. The first half of the topic of agency deals with the behavioral sense, or outward expressive evidence thereof. In behavioral psychology, agents are goal-directed entities that can monitor their environment to select and perform efficient means-end actions that are available in a given situation to achieve an intended goal. Behavioral agency, therefore, implies the ability to perceive and change the environment of the agent. Crucially, it also entails intentionality[1] to represent the goal state in the future, equifinal variability[2][3] to be able to achieve the intended goal state with different actions in different contexts, and rationality of actions in relation to their goal[4][5] to produce the most efficient action available. Cognitive scientists and Behavioral psychologists have thoroughly investigated agency attribution in humans and non-human animals since social cognitive mechanisms such as communication, social learning, imitation, or theory of mind presuppose the ability to identify agents and differentiate them from inanimate, non-agentive objects. This ability has also been assumed to have a major effect on the inferential and predictive processes of the observers of agents because agentive entities are expected to perform autonomous behavior based on their current and previous knowledge and intentions.[6] On the other hand, inanimate objects are supposed to react to external physical forces.[6]
Although the concepts are often confused with one another, sensitivity to agency and the sense of agency are distinct and separate concepts. The sensitivity to agency can be explained as a cognitive ability to identify agentive entities in the environment, while the sense of agency refers to the exertion of control over the environment and sometimes to self-efficacy, which is an individual's learned belief of how able they are to succeed in specific situations.[7]
The other half of the topic of agency deals with the arguments of determinism typically found in theories of personality and developmental lifespan. This determinism differs from philosophical determinism as it encapsulates forms of deterministic principles found within these psychological theories, such as hedonism, developmental stage theory, the law of non-contradiction, consistency, necessity, and others. Capitalizing on the first half of agency, these principles of determinism are founded on the test-retest/empirical evidence of observable behavior. Founding actors of Psychology (such as Sigmund Freud, and B.F. Skinner) defaulted on deterministic principles in order to form their theories. Much of this is due to the scientific consensus of the era, particularly concerning Newtonian principles of linear time and the attempts made by earlier psychologists to have psychology recognized as a serious science.