Hume’s Epistemology: Ideas, Facts, Causation, and Substance
Hume: Two Ways of Knowing
Hume distinguishes two ways of knowing: relations of ideas and matters of fact.
Relations of Ideas
This is the knowledge of logic and mathematics. These propositions are:
- Independent of facts, concerning only relations between ideas.
- Reached by reasoning alone, without experience.
- Necessarily true; their opposite implies a contradiction.
Matters of Fact
This is the knowledge of the positive sciences. These propositions:
- Report facts about the world.
- Are known from observation and experience.
- Are not necessarily true; their opposite is possible.
Hume’s Idea of Causation
Hume argues that our knowledge of future events is based on the cause-effect relationship. However, he criticizes the idea of cause as a necessary connection. We only observe:
- Contiguity: cause and effect are close in space.
- Succession: cause precedes effect in time.
- Regularity: cause and effect always occur together.
We do not observe a necessary connection. Therefore, causal inference is only applicable to impressions, not beyond them.
Custom and Belief
We believe the future will resemble the past due to habit or custom. This generates belief, not knowledge. Belief is a feeling, not a rigorous proof.
Hume’s Critique of Substance
Hume criticizes the idea of substance as a real substrate underlying sensible qualities. He argues:
Material Substance
The idea of substance is not based on any impression. We only perceive qualities, not a supporting substance.
Personal Substance (Self)
We have no impression of a permanent self, only a succession of perceptions.
Infinite Substance (God)
God does not correspond to any impression and cannot be proven through causality.
Substance is merely a bundle of perceptions united by imagination.
Hume’s Conclusions
Hume’s philosophy leads to phenomenalism and skepticism. Reality is reduced to phenomena, and we cannot know anything beyond our perceptions.
Summaries of Hume’s Works
A Compendium of Human Nature summarizes Hume’s Treatise of Human Nature, focusing on his empiricist theory of knowledge and its application to causality.
Aquinas’s Summa Theologica
This is a treatise on theology, using the scholastic method to demonstrate God’s existence rationally.
Descartes’s Discourse on Method
This autobiographical work reflects Descartes’s intellectual journey, emphasizing the importance of reason and method in building a new philosophy.
Aquinas’s Five Ways
These are demonstrations quia, arguing from effect to cause to prove God’s existence.