PHL105Y November 1, 2004 For Wednesday, read Descartes’s Third Meditation. Brace yourself: it is very hard. The final version of your first essay is due.

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Presentation transcript:

PHL105Y November 1, 2004 For Wednesday, read Descartes’s Third Meditation. Brace yourself: it is very hard. The final version of your first essay is due next Monday (November 8). All essays must be uploaded to turnitin.com; instructions on doing this will be available on the website.

Review: The First Meditation Descartes wants to create ‘something firm and lasting in the sciences’ He has found various old beliefs of his to be false; his old system of belief is untrustworthy He decides to wipe the slate clean and begin from the original foundations

Widening doubts Thinking about sensory illusions gives Descartes reason to doubt sense-based beliefs about small and distant things Thinking about dreams gives Descartes reason to doubt all his sense-based beliefs Thinking about the origin of his nature gives Descartes reason to doubt all his beliefs, including abstract/intellectual ones

The argument concerning the origin of my nature God exists or he doesn’t. If he exists, I have reason to doubt everything. If he doesn’t exist, I have reason to doubt everything. I have reason to doubt everything.

The evil genius Descartes decides to suppose that he is facing an evil genius, ‘supremely powerful and clever, who has directed his entire effort at deceiving me.’ Why?

The evil genius Before the evil genius comes on the stage, Descartes claims that he has found reason to doubt all of ‘the things I once believed to be true.” So the evil genius, ‘supremely powerful and clever, who has directed his entire effort at deceiving me’ does not give us any new reasons to doubt. What does he bring to the party, then?

Recap: systematic doubt Sceptical argument from… Provokes doubt about…. sensory illusionsSmall and distant things dreamingAll objects of experience (=all sense-based claims) the origin of my natureAll of my old opinions (including abstract claims based on pure intellect) the evil geniusAll of my old opinions

The Second Meditation If one supposes all one’s old opinions are in doubt, how might one proceed?

The Second Meditation If one supposes all one’s old opinions are in doubt, how might one proceed? Descartes searches for something certain, an “Archimedean point” Is there any claim that even the evil genius could not stop us from knowing?

I am, I exist The meditator is aware of his thoughts; can he infer what their source might be?

I am, I exist The meditator is aware of his thoughts; can he infer what their source might be? Could it be God? Doubtful, because perhaps the meditator himself is the source of these thoughts

I am, I exist The meditator is aware of his thoughts; can he infer what their source might be? Could it be God? Doubtful, because perhaps the meditator himself is the source of these thoughts Could it be that I too do not exist? My own existence cannot be uncertain (why?)

I am, I exist I exist, if I persuade myself of something I exist, even if the evil genius is deceiving me So I exist: ‘the pronouncement “I am, I exist” is necessarily true every time I utter it or conceive it in my mind.’

I exist: but what am I? Am I a rational animal? Could that be certain? To make it certain, I’d need to figure out what ‘rational’ and ‘animal’ meant…

I exist: but what am I? Am I a rational animal? Could that be certain? To make it certain, I’d need to figure out what ‘rational’ and ‘animal’ meant… Am I a body? (that’s dubious, although it still seems to me I know bodies better than souls)

I exist: but what am I? What is the soul, really? What can I know it to be, for sure?

I exist: but what am I? What is the soul, really? What can I know it to be, for sure? The body is doubtful, but it is certain that ‘thought exists – it alone cannot be separated from me’ So I am ‘a thinking thing’

A thinking thing For Descartes, the faculty of the imagination is the part of the soul that ponders images, whether these come from real sensations, or from memory, or from fantasy, or from dreams I can know that I am a thinking thing, even if all the deliverances of my imagination are dreams So the imagination is not required for self- knowledge; the self is known via the intellect

Imagination and intellect Problem: it seems as though the things I can imagine/visualize are clearer than the mysterious self (the ‘I’ that is grasped by the intellect) In fact it’s tempting to try to ‘visualize’ the self as being like a little fire or cloud inside you (but if Descartes is right, that can’t be a good way to gain knowledge of the self)

Imagination and intellect Descartes wants to establish that the intellect can know things with greater certainty than the imagination (because he’s achieved an intellectual result – “I exist, as a thinking thing” – even though everything the imagination tells him is still in doubt)

How much certainty could your imagination give you? Descartes imagines (perceives?) a piece of wax that is white, sweet, hard, fragrant, and makes a tapping sound when knocked on the table

How much certainty could your imagination give you? Descartes imagines (perceives?) a piece of wax that is white, sweet, hard, fragrant, and makes a tapping sound when knocked on the table When heated, the wax becomes clear, flavourless, soft, unscented, and silent What is the point of this experiment?

How much certainty could your imagination give you? If all the sensory properties change, but we still say ‘it’s the same piece of wax’, there is more to the object than its sensory properties Notice that the wax is a ‘best-case’ scenario for the imagination (even if the senses gave you tons of information, and accurately, there would be something about the wax that your senses aren’t telling you, something outside the scope of the imagination)

The intellect What is there in the wax beyond its sensory properties?

The intellect What is there in the wax beyond its sensory properties? ‘it is extended, flexible, and mutable’ Why aren’t those properties sensory? Don’t my senses tell me that that the wax is flexible as I watch it bend?

The intellect My imagination can, over time, run through many changes of shape (I can visualize the wax turning from a block to a blob); but it takes an intellect to make the purely general claim that the wax is flexible (=capable of going through countless changes); you can’t see or even imagine that something is flexible in that way; you need to think it.

What the intellect tracks Our grasp of the ‘mathematical’ properties of objects (extension, flexibility, mutability) enables us to track these objects over time even when all their sensory properties are changing These are all modal properties: they concern what the object could be and not just how it is right now (which is one reason why the senses can’t just pick them up directly)

The intellect We don’t just sense ‘white/sweet/ hard/ cold’; we think of a body which has the properties of being white, sweet, hard, cold So even in the case of the wax (which looked like a best- case scenario for getting certainty from the senses), there is more than mere sensation involved; the intellect must play a role It’s the intellect that grasps the underlying notion of body or material substance; the senses then tell us something about how that substance is affecting us

The intellect and the imagination The role of the intellect in tracking bodies is often taken for granted/overlooked We say (sloppily) that we see that there is wax; we should say that we judge that there is wax (What’s the difference?)

The intellect and the imagination When did I know the wax better? When I thought I knew it by sensation? Or when I became self-conscious about my thinking and realized the extent of the intellect’s involvement?

The intellect and the imagination If the intellect is needed even in the cases where the imagination had seemed most helpful, we should no longer be worried about which can give us more certainty

The intellect and the imagination If the intellect is needed even in the cases where the imagination had seemed most helpful, we should no longer be worried about which can give us more certainty And in particular, we should be happy with the intellect’s grasp of the self

Self-knowledge above all ‘there is not a single consideration that can aid in my perception of the wax or of any other body that fails to make even more manifest the nature of my mind.’

Self-knowledge above all ‘there is not a single consideration that can aid in my perception of the wax or of any other body that fails to make even more manifest the nature of my mind.’ Every judgment about anything simultaneously proves something about myself (Why? How?)