英国留学

Meditation I
Things which can be called into Doubt

• Descartes rejects all his beliefs about the external world because they are doubtful and he wants to find a foundation that is indubitable to fix his beliefs on
• His arguments for universal doubt  

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Critical Analysis of Descartes Method

• Is immunity from doubt a criterion for knowledge?  

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Conclusion
Descartes method on the surface looks good to get rid of all the dubious beliefs and then only have a firm foundation. However, he takes his doubt too far and at times is becoming a global skeptic which is an illogical position to hold (doubt requires certainty). Crucially,

his criterion for knowledge is undoubtablity and as shown this is not an epistomogical method for certainty and a certainty could be wrong.

Meditation II
Of the Nature of the Human mind; and that it is Easier to Know than the Body

Cogito

• I am; I exist (I think therefore I am – Discourse)
• This proposition is necessarily true every time I express it
• The mere fact that I am able to doubt my own existence means that I am here to doubt and thus I must exist.
• This is the point of foundation that Descartes will no build upon
• Surely it must be true that any thought requires a thinker, what exactly would 'just' a thought be? Every attribute must have a substance. 

Problems

• Hume said when he inspected his thoughts he was aware of no 'I'
• Pre-supposes an 'I' to exist, the premise contains the conclusion.
• Lictenburg – 'there are thoughts, therefore thoughts'
• Surely if he was being a through skeptic the evil demon could deceive him about this
  

 The Wax

• Take a piece of wax – it is hard cold and makes a sound
• Put the same wax by the fire, the smell, the color, the shape etc. are all destroyed
• All the sensations about the wax change yet we maintain it is still the same
• Perhaps this is because I can imagine the wax in all its forms, yet we are stuck as I could not possibly imagine all the infinite forms!
• So since I do not know the wax through the imagination or the senses, then it is clear that the wax must be understood through the understanding only
• Therefore it is clear to see that there is nothing easier to know than my mind.

Shows

• We have a mental operation thus confirming the cogito
• Some truths are a priori (rationalist)
• There is a distinction between the mind and the body
• I am essentially just a thinking thing

Problems

• Just because it is conceptually possible that the mind/body are distinct does not mean it is an ontological issue, in fact modern science has shown the brain can affect the mind.
• Water + H2O, conceptually two things, ontologically the same
• Husband + Wife, conceptually connected, ontologically two things
• Surely the senses at least in some respect must be used to grasp the wax – both are not required just understanding.
• Is all our knowledge essentially a priori, how can we accept such radical rationalism – we must at least engage with the world to understand it. Experiments are necessary in the sciences.

Meditation III – of God; that he exists
Trademark Argument

• A cause must be up to its effect, either eminently or formally. For instance something cannot cause heat if it is not hot etc.
• There are two different realities, firstly we have REPRESENTATIONAL REALITY* which are ideas in the mind
• Secondly, we have FORMAL REALITY which are actual things
• These can be ranked in an order such as 'God -> Human -> Tree'
• Since the cause must be up to the effect and humans are finite, and we have the idea of God within us who is infinite and we could not have caused him – that clearly this idea must have come from outside us
• The only thing that has enough formal reality to cause an idea of God is God himself and thus, God must have given humans the idea of him.
• Therefore, God exists.
• This reality may be translated as objective/intentional/representation.

 Strengths

• As a basic principle, the cause must be up to the effect, for instance we cannot ever build a Nuclear Power Station out of string

 Problems

• Although the above may be true, it is a different story when applying cause and effect to ideas – it is surely possible that although we couldn't make 'God' we could conceive of him
• We can conceive of beings with more 'representational reality' that us by negating our finite qualities

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• Science has undermined the cause and effect principle by showing that it may be possible for something to come from nothing.
• What exactly is 'more reality' how can something have 'more reality/existence' – seems absurd

 Meditation V
Of the Essence of Material Things; and, once more of God, that He exists

Ontological Argument

• If I conceive a shape, it has certain immutable truths about it (Pythagorastheorem)

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• No, as I can imagine shapes I have never experienced and still work out truths of them
• God is the most supremely perfect being
• Existence is a perfection
• Trying to separate existence from God is like trying to separate a mountain from a valley.
• Therefore, God must exist (a priori analytic truth)

 Problems

• Existence is not a predicate (Kant)  

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Meditation VI
The existence of material things, and the Real distinction between the soul and the body of Man

Imagination

• When I imagine something, it is present to my mind
• Imagination is distinct from thought

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• Effort is required for imagination, but not for thought
• Imagination is not essential to me, I can exist without it
• Thoughts turn to your own ideas, yet imagination to your body
• Imagination seems to require the existence of a body – not for certain thought.

 Problems

• Again, the issue of conceptually to ontological. Just because I can think I exists without an imagination does not mean it is not essential ontologically to me

Reasons for thinking that material objects exists

• Ideas appeared against my will
• All ideas from the imagination come from the senses
• I sense pain and pleasure in my body, but not objects external to me  

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Mind Body distinction

• The mind is divisible while as the body isn't (can't have ½ a thought)
• Argument from knowledge  

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Material Objects exist

• I have ideas come to me against my will (of external objects etc.)
• This faculty is in something other than myself
• This something must have as much reality as the intentional reality it produces
• This could only be done by God or res extensa
• God is not a deceiver
• Therefore, material objects exist

Mind Body relation

• I am not like the pilot in the ship who would not feel if he crashed into an iceberg, I am intimately joined to my body due to experiences of pain and pleasure
• It therefore must be that both our minds and bodies are intermingled with each other
• SUBSTANCE DUALISM
• X is a mental state, Y is a physical state
• It is logically possible that X exists and Y does not [not contradictory]
• Therefore X is not the same as Y – thus they must be separate.
• Leibniz's Law – Identity of indiscernible

Problems

• How do the two parts interact with each other? A contemporary philosopher coined Descartes Dualism the 'ghost in the machine'. It seems impossible to understand how the non-physical can interact with the physical – for instance, how does the desire to type this make me type it?
• The issue of conceptual vs. ontological, we can imagine that the mind is distinct, yet modern science has shown that the mind appears reliant on the brain.
• Are the mind and body really distinct? Some of Descartes arguments for distinction actually fail but also with modern philosophy now centering on a materialist approach to the mind/body problem and science going someway toward showing how the physical alone can cause supposed 'mental states' – this is starting to undermine his theory

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