Aristotle’s Theory of Change and the Soul
Principles of Change
To understand movement, three principles are required: substrate, form, and privation. In every change, something remains (the substrate), and something changes. The substrate becomes a form it previously lacked (privation). For example, an illiterate person becoming literate: the man is the substrate, illiteracy is the privation, and literacy is the acquired form.
Hylomorphic Theory
Relating these principles to hylomorphic theory, matter is the indeterminate substrate where change occurs. Privation is the starting point, the unfulfilled potential, and the form is the endpoint, the realization of that potential. Individuals change by increasingly realizing their form (e.g., humans realizing rationality through knowledge).
Act and Potency
Act and Power
Act is the current state of being, while potency is the potential to become something else. Movement is the transition from potency to act, driven by a teleological purpose (telos, end).
Causes of Change
The Causes of Change
Aristotle identifies four causes of change:
- Material Cause: The material or substrate of change.
- Formal Cause: The form achieved through change.
- Efficient Cause: The initiator of the change process.
- Final Cause: The purpose or goal of the change.
The Unmoved Mover
The Unmoved Mover
For change to occur, an engine must initiate it. In natural beings, the form acts as both efficient and final cause. However, a Prime Mover is necessary to initiate all movement without being moved itself. This Unmoved Mover is pure act and the final cause of all movements.
The Soul as Form
The Soul as a Body
Aristotle views nature as a hierarchical system, with inorganic nature, plants, animals, and humans forming an organized whole aiming towards the Pure Act.
Unlike Plato, Aristotle believes the soul is the body’s form, not separate from it. The soul actualizes the body’s potential, making it function. The soul cannot exist without the body; the composite of body and soul is the substance.