Hume’s Empiricist Philosophy: Knowledge and Morality
Hume’s Philosophy: Pragmatism and Morality
Hume’s philosophy represents a double inversion concerning traditional views: To verify theory, we need practice (accepting beliefs vital for human life), which foreshadowed twentieth-century pragmatism. By basing knowledge solely on impressions, he completely denies religion as a foundation for morality, anticipating one of the main themes of Enlightenment thinking.
Compare:
- Objectivism: Socrates, Plato
- Relativism: Sophists (e.g., Protagoras)
In principle, Hume aspires to ethical objectivism, betting optimistically (in an Enlightenment fashion) on a universal ethical sentiment. However, since his ethics are based on emotions and feelings, the universality of these feelings is debatable.
Finally, two contributions distinguish Hume in the history of philosophy:
- A concern for clarifying the exact meaning of terms by showing their empirical basis.
- An illustration of the philosophical problems encountered when analyzing the consequences of what seems like a sound principle of common sense: we know only what is experienced and only to the extent that it is experienced.
Hume’s Empiricism and Key Critiques
Hume is an empiricist philosopher, belonging to the philosophical current stating that the only valid knowledge comes from experience. The foundations of empiricism were laid by philosophers such as Locke, Berkeley, and Hobbes, and brought to their conclusion by Hume. While Hume affirmed the validity of experience as the origin of knowledge, Locke postulated the existence of material substance, and Berkeley thought God sent the impressions to our minds.
This current is contrasted with rationalism, which asserts that reason is the sole source of knowledge.
Epistemology: The Role of Consciousness
For Hume, the worldview human beings possess results from an organized succession of perceptions taking place in consciousness. Three elements are involved in knowledge: consciousness, impressions, and their organization.
Consciousness
Consciousness includes everything the human being is aware of. Do the contents of consciousness faithfully represent external reality? Hume calls the contents of consciousness perceptions.
Impressions and Ideas
Hume distinguishes between impressions and ideas. Impressions correspond to the information provided by our senses. For example, my consciousness receives different impressions from the review I’m reading: color, size, etc. If I close my eyes, though, this sensory information disappears.
Ideas are derived from impressions; they are fainter copies. Hume further distinguishes two types of reasoning or propositions:
- Relations of Ideas: Discoverable by thought alone (e.g., geometry, algebra). Their negation implies a contradiction.
- Matters of Fact: Known through experience (e.g., the sun will rise tomorrow). Their negation is conceivable.
These distinctions echo the rationalist philosopher Leibniz’s concepts. Later, Kant would speak of analytic and synthetic propositions.
Critique of Causality and Substance
Two of the most important concepts Hume analyzes are causality and substance.
Causality
Regarding the former: while for Berkeley, Descartes, and Locke, causality might potentially overcome subjectivity, for Hume, it is merely the result of mental habit or custom. We observe constant conjunction, assume necessary connection, but have no impression of the connection itself. Causality is thus a belief, not certain knowledge.
Substance
Regarding the latter, Hume criticizes the three prevailing ideas about substance in his time:
- Aristotle’s idea: If substance is the underlying reality, Hume argues this is unlikely because all our impressions would then have to be substances, which seems absurd.
- Locke’s idea: If substance is the unknown support of sensible qualities, Hume counters that impressions cannot refer to anything other than themselves. We have no impression of this supposed support.
- Metaphysical Substances: Based on core empiricist principles, Hume argues we have no impressions of an infinite substance (God) or a thinking substance (the self or mind as a unified entity). Therefore, we cannot affirm their existence based on experience.
Thus, for Hume, the concepts of substance and causality are rational beliefs, necessary for life and science (like physics), but not grounded in empirical certainty. Beliefs about God’s existence, previously cemented by philosophers like Descartes and Saint Anselm who argued for the necessity of a higher being to make sense of the world, are similarly undermined by Hume’s strict empiricism.