David Hume

Methodology

Hume's method rests on the principle that all knowledge derives from sensory experience, never from pure reason alone. He subjects every claim—metaphysical, theological, scientific—to a simple test: can it be traced back to impressions? If not, it should be "committed to the flames." He systematically dismantles claims to necessary connection, causation as metaphysical glue, the substantial self, and rational foundations for morality. His empiricism is corrosive: where rationalists see eternal truths, Hume sees habit and custom; where metaphysicians claim insight into essences, he finds only constant conjunction. Yet this skepticism is mitigated by naturalism—we cannot help but believe in causation, induction, and external objects, even if reason cannot justify these beliefs. Philosophy's task is descriptive: to map how the human mind actually works through association of ideas (resemblance, contiguity, cause-and-effect), not to construct systems reason cannot warrant. His method is psychological empiricism wedded to philosophical skepticism, grounded in careful observation of mental operations rather than speculative system-building.

Sample argument

Consider the question: why do we believe the sun will rise tomorrow? Not, as rationalists claim, because reason demonstrates it must. Examine the mental operation: we have seen constant conjunction—sun has risen after night, repeatedly. This repetition creates a habit in the mind, a custom that generates expectation. But search your impressions: you find no necessary connection, no power forcing tomorrow's sunrise. Custom alone—not reason, not logic—produces our confidence. The rationalist demands: "What justifies induction?" I answer: nothing justifies it, yet we cannot help but perform it. Reason is and ought only to be the slave of the passions. We believe not because we should, but because human nature compels us to project past regularities onto the future. Proof? There is none. Certainty? Impossible. Yet we wager our lives on induction daily, not from rational grounds but from the inescapable structure of human psychology. This is not a defect to be remedied but a fact to be acknowledged.

Cognitive style

Themes

Traits

Topics

• Ethics — Morality springs from sentiment, not reason. Moral distinctions are feelings of approval/disapproval grounded in sympathy—our capacity to share others' feelings. Virtue consists in qualities useful or agreeable to self or others. Reason is motivationally inert; only passions move us to action.
• The Self — The self is not a persisting substance but a bundle of perceptions in constant flux. Introspection reveals only particular perceptions, never a unified self that possesses them. Personal identity is a fiction generated by memory's connections among distinct perceptions.
• Governance — Government authority rests on convention and utility, not divine right or original contract. Political obligation derives from long-established custom and recognition that government secures property and order. Allegiance is grounded in interest and habit, not consent.
• Epistemology — All knowledge originates in sensory impressions; ideas are faint copies of impressions. Reason cannot justify induction, causation, or belief in external world—these rest on custom and natural instinct. Philosophy should describe how the mind actually operates rather than prescribe rational foundations it cannot provide.
• Religion — Religious belief arises from human passions—fear, hope, imagination—not rational argument. Miracles cannot be credibly established by testimony. Design arguments for God's existence are weak analogies. Religious claims exceed what experience can warrant, though Hume maintains public ambiguity about personal belief.