agent causation the idea that the primary cause of an event is a substance; more specifically, causation by a substance, as opposed to an event. Thus a brick (a substance) may be said to be the cause of the breaking of the glass. The expression is also used more narrowly by Reid and others for the view that an action (or event) is caused by an exertion of power by some agent endowed with will and understanding. Thus, a person may be said to be the cause of her action of opening the door. In this restricted sense (Reid called it ‘the strict and proper sense’), an agent-cause must have the power to cause the action or event and the power not to cause it. Moreover, it must be ‘up to’ the agent whether to cause the event or not to cause it. (It is not ‘up to’ the brick whether to cause or not to cause the breaking of the glass.) The restricted sense of agent causation developed by Reid is closely tied to the view that the agent possesses free will.
Medieval philosophers distinguished the internal activity of the agent from the external event produced by that activity. The former was called ‘immanent causation’ and the latter ‘transeunt causation.’ These terms have been adapted by Chisholm and others to mark the difference between agent causation and event causation. The idea is that the internal activity is agentcaused by the person whose activity it is; whereas the external event is event-caused by the internal activity of the agent.
See also CAUSATION, FREE WILL PROBLE. W.L.R.