Hume’s Epistemology: Impressions, Ideas, and Skepticism

Theory of Knowledge: Elements

All knowledge of the mind are perceptions, in two types:

  • Impressions: Perceptions from the senses, simple or complex.
    • Simple: Captured by a single sense.
    • Complex: Apprehended through multiple senses.
  • Ideas: Memories of past impressions, simple or complex.
    • Simple: Result from a single impression.
    • Complex: Formed by associating simple ideas (similarity, contiguity, cause and effect).

Impressions are stronger and precede ideas. Thought derives from sensitivity.

Hume’s Empiricism:

  • Simple ideas derive from impressions.
  • Validating an idea requires identifying its originating impression.

Complex ideas are harder to trace to specific impressions.

Types of Knowledge

Understanding combines knowledge and relates ideas, forming two types:

  • Relation of Ideas: Interlinked ideas, truth independent of experience, denial is impossible.
  • Matters of Fact: Based on experience, truth is empirical, denial is possible.

Critique of Causality

Human knowledge is limited to past and present. Future projections rely on causal inferences, assuming a necessary connection between events.

Hume argues we only observe constant conjunctions, not necessary connections. Predicting the future is impossible.

The Reality: External, God, and Self

Hume questions the existence of external reality, God, and the self.

External Reality: We lack impressions of substances causing perceptions, making belief in an independent reality unjustifiable.

God: The idea of God lacks sensory impression and rational justification.

Self: We have no constant impression of a fixed self, only a succession of perceptions linked by memory.

Phenomenalism and Skepticism

Phenomenalism reduces reality to phenomena, denying substances.

This leads to moderate skepticism, doubting beyond sensory perceptions. It promotes tolerance due to the uncertainty of knowledge.