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Agency is the capacity of an actor to act in a given environment. The capacity to act does not at first imply a specific moral dimension to the ability to make the choice to act, and moral agency is therefore a distinct concept. In sociology, an agent is an individual engaging with the social structure. Notably, though, the primacy of social structure vs. individual capacity with regard to persons' actions is debated within sociology. This debate concerns, at least partly, the level of reflexivity an agent may possess.
Agency may either be classified as unconscious, involuntary behavior, or purposeful, goal directed activity (intentional action). An agent typically has some sort of immediate awareness of their physical activity and the goals that the activity is aimed at realizing. In ‘goal directed action’ an agent implements a kind of direct control or guidance over their own behavior.
Agency is contrasted to objects reacting to natural forces involving only unthinking deterministic processes. In this respect, agency is subtly distinct from the concept of free will, the philosophical doctrine that our choices are not the product of causal chains, but are significantly free or undetermined. Human agency entails the claim that humans do in fact make decisions and enact them on the world. How humans come to make decisions, by free choice or other processes, is another issue.
The capacity of a human to act as an agent is personal to that human, though considerations of the outcomes flowing from particular acts of human agency for us and others can then be thought to invest a moral component into a given situation wherein an agent has acted, and thus to involve moral agency. If a situation is the consequence of human decision making, persons may be under a duty to apply value judgments to the consequences of their decisions, and held to be responsible for those decisions. Human agency entitles the observer to ask should this have occurred? in a way that would be nonsensical in circumstances lacking human decisions-makers, for example, the impact of comet Shoemaker–Levy on Jupiter.
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