Reid argues that causality requires more than just physical conditions; it requires the free will of the actor. In his view, the true cause is human will, and the physical events are merely effects.
Suppose a red ball hits a stationary white ball, causing the white ball to move. Hume laid out three requirements for a causal relationship between the red ball hitting the white ball and the white ball moving. The cause must precede the effect in time, the cause and effect must follow each other in space and time, and there must be an “invariant union” between the cause and effect. Homeostatic coupling means that if two balls move and collide in the same way under similar circumstances, they will behave in the same way. This concept is consistent with our everyday experience, and we often infer a causal relationship when we see similar results under similar conditions.
However, Reid believes that even when Hume’s three conditions are met, such as in the example above, causation is not established: only an agent with free will can be the cause. This is a view that goes beyond the relationship between mere physical events, and that true causation only occurs when human will and action are involved.
In actor-causation theory, Reid characterized causes as entities that have “ambivalent capacities” and are responsible for their changes. An ambivalent capacity is an active ability to produce or not produce change, and an actor is an entity that possesses the capacity to produce an outcome, can exercise that capacity, and can be held responsible for that change. Reid argues that the true cause is the actor. According to him, when a red ball hits a white ball, the red ball cannot be an agent because the white ball can only move, not not move.
From Reid’s perspective as an empiricist, the only agents within the scope of observation are humans. If a person rolls a red ball to make a white ball move, and the white ball moves, then the person is an agent and the movement of the white ball is an effect. In Reid’s view, for an outcome to occur, the agent must be ambivalent, and the agent’s motivations must be in constant conjunction. Reid saw volition as an event in the mind. This emphasized that the human will is a special capacity that transcends simple physical laws of causation.
In this regard, it can be argued that a volition that is coupled to the exercise of an ambivalent faculty that produces an outcome is a manifestation of another ambivalent faculty, which requires another volition. In response to this argument, Reid argues that an intrinsic activity of the mind, such as the will, is indistinguishable from the exercise of the agent’s ambivalent faculty, the “causing of the will,” and the result, the will itself. This suggests that in the case of causing a will, the exercise of the agent’s faculty is itself a will and does not require another will. However, a counter-argument to Reid’s view that volition and event are always conjoined could be that the cause of the event is the volition, not the agent. In response, Reid supported his theory by arguing that an invariant union alone does not justify causal necessity.
Reid also had to address the problem of “chance causes. At the time, some philosophers, influenced by medieval philosophy, believed that only God was the true cause of events, including human behavior, and that agents were merely chance causes. An opportunistic cause is something that appears to be a cause in everyday life but is not actually a true cause. For example, when a person is cured of an illness through prayer, the prayer itself did not cause the illness, but God did. Reid rejected this position from an empiricist perspective, arguing that God cannot be the true cause of an event because all we can experience are the motivations and actions of agents, and divine intervention in an action is something that cannot be experienced. Reid emphasized the implications of human agency by arguing that it is ultimately up to the agent to make decisions. In doing so, Reid emphasized the importance of human free will and responsibility, making it clear that humans are not simply passive beings driven by external factors.
In conclusion, Reid’s theory of agentic causation provides a philosophical perspective that emphasizes human free will and responsibility, rather than simply viewing causation as a physical chain of events. It provides a framework for a deeper understanding of the causal relationships we experience in our daily lives, and it invites us to reconsider the importance of human behavior and moral responsibility.