Western Metaphysics: Substance, Causality, Mind and Body, Freedom
Four problems
The paper tests four connected metaphysical issues: substance, causality, mind–body relation, and freedom.
Core positions
- Substance: Aristotle's primary substance is the individual; Descartes has two created substances, res cogitans and res extensa; Locke's substratum supports properties; Hume denies any impression of substance.
- Causality: Hume reduces cause to constant conjunction and custom; Kant treats causality as an a priori category; powers/dispositional views hold causal powers are real.
- Mind–body: substance dualism (Descartes), materialism/identity theory (mind = brain), behaviourism, functionalism.
- Freedom: hard determinism denies free will; libertarianism affirms contra-causal freedom; compatibilism reconciles freedom with determinism by defining freedom as acting on one's own desires without external constraint.
Worked example
Hume on billiard balls: we observe ball A moving, then ball B moving; we never perceive a necessary connexion. The idea of cause arises from repeated conjunction and habit. Therefore causal necessity is not given in experience. Criticize: constant conjunction may be evidence for causal structure, but Hume's point is about the origin of the idea.
Traps
Do not confuse correlation with causation. Do not call compatibilism 'no freedom'; it redefines freedom. Do not treat identity theory as dualism. Do not say Hume denies causation altogether; he analyses its meaning empirically.