Descartes

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Meditation 1

Summary of content - what can be called into doubt

Descartes' strategy

demolishing all his beliefs and starting again from the foundation

seeking to find absolutely certain knowledge

therefore, he is suggesting he destroys all his previously trusted beliefs and begins anew with secure and trusted beliefs that can be built upon to create a firm structure

approach involves two aspects:

he will not accept as true anything that he is able to doubt even a little bit

he will consider the basic principles upon which all his beliefs are based

Part 1: the unreliability of the senses

many of the beliefs he has taken to be completely reliable come from his sense experience

considers the fact that his senses have been shown to deceive him

it might be wise not to trust in them completely

P1: My senses have deceived me in the past

P2: it is wise not to have complete trust in something that has previously deceived you

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C: i should not have complete trust in my senses

not that the senses are absolutely untrustworthy but that he should not have complete trust in his senses

The difficulty of doubting some sense information

many beliefs gained from sense experience that he finds impossible to doubt

example of himself sitting by the fire in his dressing gown

he is comparing someone who would doubt the reliability of such beliefs based on sense experience with a person who is deranged and believes they are made of glass

dismissing the possibility that all sense experience should be completely doubted

The dream argument

descartes points out that his waking experience seems very distinct and vivid

could give him reason to be certain of his wakefulness

he then questions this when remembering that he has thought very similar thoughts in his sleep

he supposes that there are no clear signs by which it is possible to tell when you are awake rather than asleep

P1: there are no certain signs that distinguish my waking life from being asleep and dreaming

P2: if there are no certain signs that distinguish my waking life from being asleep and dreaming, then it is possible that I am not awake right now but rather dreaming I am awake

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C: it is possible that I am not awake right now but rather dreaming I am awake

it is possible he could be dreaming now

he may not even have a body of any sort at all

if he is dreaming, there must be at least some things that his dreams are based upon that are still real

Things that might survive the dream argument

colours

matter or physical substance

extension

shape

quantity

size

time

place

Provisional conclusion

subjects like physics, astronomy and medicine cannot be reliable

these ideas may be the product of our dreams and so we cannot trust in them

subjects like geometry and arithmetic as being possibly trustworthy

arithmetic deals solely with numbers

geometry deals with numbers and shapes

'whether I am awake or asleep two and three added together are five, and a square has no more than four sides.'

even if he is dreaming Descartes supposes that there are still some basic truths that he cannot doubt

The deceiving God argument

continues his meditation to consider the idea he has of God

it is possible that an all-powerful God could make it seem to him as though there were such things as sky, earth, size, shape, etc. when in fact there were no such things

'How do I know that God has not brought it about that I too go wrong every time I add two and three or count the sides of a square?'

if there is an all-powerful God, even the basic principles that held firm after the dream argument could now be uncertain

Problems with the counter objection that God wouldn't do that

considers the possibility that deception might be seen to be inconsistent with the concept of a supremely good God

he rejects this idea because he argues that, if we think such deception is inconsistent with the goodness of God, then we should also consider any deception at all equally inconsistent with God's goodness

P1: if it is inconsistent with the goodness of God to create a person such that they are deceived all the time, then it would be equally inconsistent to create a person who is deceived even occasionally

P2: I am deceived occasionally (Descartes does not specify this here but presumably he is thinking of how the senses deceive us)

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C: it is not inconsistent with the goodness of God to create a person that may be deceived all the time

may be possible that there is an all-powerful God who could deceive him about even the basic principles

Even saying there is no God doesn't solve the problem

he also recognises that not all those who might undergo the process of meditating will have such a firm belief

claims that if there is no God then we might think ourselves even more likely to be in a state of complete deception

Seite 2

Meditation 2

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Method of Doubt Revision Sheet

Introductory Comments

This is found in the 1st Meditation. Descartes is not a sceptic but is using a sceptical approach to sow that it is untenable. It is designed to target some of the main sources of knowledge relied upon by the scholastic approach:

authorities

sense experience

reason

He is aiming to establish a level of certainty for all knowledge similar to that we obtain in geometry and maths.

Outline of his approach:

he will doubt everything

assume nothing is true

re-examine all of his beliefs

will focus only on foundational beliefs - sense experience, a priori belief, etc.

if these fall then anything built on them falls

reject obvious falsehoods

also reject the slightest doubts

barrel of apples analogy

looking for a secure foundation

architectural metaphor - knowledge is like a building which requires a solid 'bedrock of truth' on which to build

Putting the Method into Practice

A) Argument against Authorities

mentioned briefly in the Meditations

things taught him by teachers in the past have turned out to be false

'disagreement of the learned' also suggests that even they can be mistaken

hence it is never advisable to simply accept things based on who said them

B) Arguments against Sense Experience

objects at a distance appear smaller than they really are

very small objects do not reveal their true detail

other arguments from illusion: oar in water, phantom limbs

however, apart from these, aren't my senses mostly reliable?

C) The Dream Argument

any given piece of sense experience can be replicated in dreams

even the belief that I am sitting by the fire could be an illusion

the phenomenon of false awakenings exacerbates this concern

however, maths and geometry seem immune: even when asleep 2+2=4

D) The Demon Hypothesis

the ultimate in scepticism: an argument against a priori beliefs

a device which will prevent him sliding back into his familiar beliefs

imagine an evil demon fooled you about everything we see and think

could anything pass such a severe test for certainty?

E) The Cogito

terminates the search for knowledge

even if dreaming I must exist to dream

even if being fooled I must exist to be fooled

at last he finds his bedrock of truth

Comments and Criticisms of the Method

Descartes doesn't doubt the reliability of his memory when he says he 'remembers occasions he has dreamed in the past'

neither does he doubt the reliability of the laws of logic: he can't construct his arguments without them, yet they could be deceptions of the demon

he doesn't doubt the consistency of language: he couldn't communicate with us or even himself if the meanings of words were constantly interfered with by the demon

if we are careful how we describe our sense experiences then are they fooling us? Our eyes merely tell us that the building appears smaller, not that it is smaller

he can't prove that we are always dreaming - if so the concepts of 'dreaming' and 'awake' would be meaningless

can't we distinguish dreams from reality? dreams are fragmented and bizarre, reality is continuous and mundane

is any other knowledge capable of the certainty we find in maths?

is Descartes' foundationalist assumption correct? does certain knowledge need a foundation on which to base all our beliefs? couldn't knowledge be okay so long as it is coherent and internally consistent? (Bertrand Russell)

Defences

according to his method, he needn't prove that our sources of knowledge are never reliable, only that they occasionally deceive in order question them

he is not recommending this method as an approach for everyone, just as a once in a lifetime exercise

we mustn't take Meditation 1 out of the context of the whole book - he later defends sense experience in Meditation 6

he also provides counter arguments to the dreaming arguments later on

Russell's Coherentism is controversial and brings its own attendant problems

Conclusion

He provides a reasonable evaluation of possible sources of knowledge, which makes sense in the context of his book. The real issue is whether anything, even the cogito, escapes his hyperbolic doubt.

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Meditation 2 - Revision Sheet

Summary and Evaluation

The cogito is striking and at first glance appealing - I can't doubt that I am thinking because doubting is a form of thinking. However, there is a problem of how we should interpret or understand the certainty of the cogito. Is it a logical argument or is it merely an intuition? Some interpretations seem to depend on the validity of either experiential or rational arguments - both of which Descartes has already dismissed. Is it a dead end? The only way we can progress from the cogito is to employ the 'clear and distinct rule' to identify other intuitively certain beliefs. However, the clear and distinct rule arguably involves Descartes in the 'Cartesian Circle' of justifications. Does the cogito