Descartes and Hume: Foundations of Knowledge and Skepticism in Philosophy

What is the general goal of Descartes' Meditations?

To establish a foundation for knowledge that is absolutely certain, beyond all doubt.

What is Descartes' method in Meditation I?

Methodological (hyperbolic) doubt — doubting all beliefs, even unreasonable ones, to find certainty.

What is the Dream Argument?

The possibility that we are dreaming shows sense experience cannot provide certainty, since dreams can mimic reality.

What is the Deceiver Argument?

The idea of an all-powerful deceiver (evil demon) suggests even reason and math could be doubted, leaving nothing certain.

What is Descartes' famous conclusion in Meditation II?

Cogito, ergo sum — 'I think, therefore I am.' [cite: 224]

What does the Cogito Argument prove?

That the existence of the self as a thinking thing cannot be doubted, because doubting itself is a form of thinking. [cite: 225]

What is the nature of the self for Descartes?

The self is a thinking thing (a mind), distinct from the body.

What does the Wax Example show?

Bodies are not known by the senses or imagination, but by the understanding alone. [cite: 227]

Knowledge of physical things comes through the mind, not senses. [cite: 228]

What is the difference between a priori and a posteriori knowledge?

A priori = knowledge independent of experience; [cite: 229]

A posteriori = knowledge dependent on experience. [cite: 230]

What is foundationalism?

The view that knowledge must be built on a foundation of absolutely certain beliefs.

What is the difference between essential and accidental properties?

Essential = properties something must have to be what it is; [cite: 232]

Accidental = properties it can lose without ceasing to be itself. [cite: 233]

What is Cartesian dualism?

The distinction between mind (thinking, non-extended) and body (extended, non-thinking).

What is rationalism?

The view that reason is the primary source of knowledge (contrasted with empiricism).

What are the two classes of mental perceptions in Hume's philosophy?

Impressions (vivid, original experiences) and Ideas (fainter copies of impressions). [cite: 236, 237]

What is the source of all ideas according to Hume?

Sense experience; reason alone cannot create ideas.

What is Hume's argument against innate ideas?

All ideas trace back to prior impressions; no idea exists without an originating impression.

What are the two objects of human reason, according to Hume?

Relations of Ideas (necessary truths, like math) and Matters of Fact (truths about the world, learned from experience).

What are Matters of Fact based on?

The relationship of cause and effect.

Why is reasoning about Matters of Fact uncertain?

It relies on induction — assuming the future will resemble the past. [cite: 243]

What is Hume's skeptical problem with induction?

There is no rational justification for believing the future will be like the past; [cite: 244]

assuming it is so is circular reasoning.

How does Hume describe reasoning about cause and effect?

Probability-based, not certain knowledge.