Understanding Hume’s Philosophy
Hume’s Philosophical Goals
Hume shared Locke’s interest in moral philosophy and admired Newton. His aim was to study the science of human nature and unify all sciences through empirical analysis.
Theory of Knowledge
Perceptions
Everything in the mind is a perception. There are two kinds:
- Impressions: Strong, vivid perceptions like sensations and emotions.
- Ideas: Faint copies of impressions, less intense.
Both can be simple or complex. Simple impressions create simple ideas, and complex impressions create complex ideas. No impression, no idea.
Relations of Ideas and Matters of Fact
- Relations of Ideas: Necessary truths based on the principle of contradiction (e.g., mathematics).
- Matters of Fact: Contingent truths based on experience and the principle of causality (e.g., natural sciences).
These are irreducible to each other. Empirical knowledge, though not rational, is essential for understanding the real world.
Critique of Rationalist Metaphysics
Causality
All reasoning about reality relies on causality. Hume analyzed it based on:
- Spatial-temporal contiguity
- Temporal priority of cause
- Constant conjunction
Causality is based on habit and belief, not reason. We expect the future to resemble the past.
Substance
Hume rejected the idea of substance beyond impressions. We have no impression of self, God, or substance. Substance is a meaningless term not reducible to experience.
Certain knowledge of future events is based on belief, not universal truths. Causality has a psychological basis, challenging Cartesian metaphysics.
Moral Philosophy
Reason cannot determine moral judgments. Morality is based on sentiment, approval, or disapproval. The will is a mode of desire. Reason serves passion, which seeks happiness and avoids suffering. Sympathy allows us to understand others’ feelings.