Book 1, Part 4:

Section 3: Of the [errors of the] ancient philosophy

What mistake did the ancients make? To think that the mind can distinguish a substance from its accidents.

Here Hume returns to his attack on substance, which he attributes to the imagination’s tendency “to feign something unknown and invisible” an “unintelligible something”(1.4.3.4)

Section 4: [The corresponding errors] of the modern philosophy

What corresponding mistake do modern philosophers make?

To think they can distinguish primary qualities (qualities in the object) from secondary qualities (qualities of our perceptions).

How does Hume attempt to undermine the primary/secondary quality distinction?

Section 5: Of the immateriality [or materiality] of the [mind].

The two views that Hume opposes: That the self is a material substance and that the self is an immaterial substance.

Hume makes the familiar argument that we can have no idea of substance. He makes a second argument that the variety of our perceptions is such that they could not all inhere in any one kind of substance, whether material or immaterial.

Conclusion: There are only perceptions and causal relations between them.

The self is a bundle of perceptions.

Section 6: Of Personal Identity [and the Self]

The problem: How could we ever get the idea of a self that is the same over time, when our perceptions change constantly?

The self is not a substance. What is it?

A "biass of the imagination"(T 1.4.6.6)

The example of the ship (of Theseus)

The example of the oak tree. Does this example make Hume’s point? What about a caterpillar that turns into a butterfly?

Why aren’t these counterexamples to Hume’s theory of identity?

"The identity, which we ascribe to the mind of man, is only a fictitious one"(T. 1.4.6.15)

Personal identity is not the result of an impression of the senses, but an impression of reflection.

The two factors that create the illusion of personal

identity: memory and mental causation.

"The question is, how far we ought to yield to these illusions [of the imagination]."(T 1.4.7.6)

Appendix: Hume's acknowledgment of an inconsistency in his account of personal identity. There is disagreement about what the inconsistency is. Talbott's suggestion: Hume realizes that he has no account of which bundles of perceptions are selves, because there are no real causal relations between perceptions.

Example: We normally suppose that what makes a memory a memory is that it was caused by a past perception. Hume cannot appeal to such real connections. So consider a set of twins, Mo and Joe, who grew up together and had many of the same memories. On Jan. 1, 2009 Mo lost his memory. Consider the bundle of perceptions that includes Mo’s perceptions before Jan. 1, 2009 and Joe’s perceptions after that date. Call that combination MoJoe. MoJoe’s perceptions have more continuity that Mo’s actual perceptions before and after Jan. 1, 2009, so why isn’t MoJoe a self? [Don’t say that Joe already claims them? Why can’t two selves overlap in this way?]

One of the great puzzles of Hume’s philosophy is that after he dismisses the idea of the self as a fiction, he uses it so extensively in Books 2 and 3.

Section 7. Conclusion

What kind of skeptic is Hume?

What have we learned in Book 1 about human knowledge and belief?

Reason is replaced by "strong propensity" to believe.

Inference is "so little founded on reason"(T 1.4.7.3)

Foundation is the imagination, the vivacity of our ideas.

The Main Normative Question: How far ought we to yield to the illusions of the imagination?

The contest between philosophy and superstition.

Hume, the true sceptic, not the despairing skeptic.

“A true sceptic will be diffident of his philosophical doubts, as well as of his philosophical conviction; and will never refuse any innocent satisfaction, which offers itself, upon account of either of them.”[T1.4.7.14]