Philosophy 4610

Philosophy of Mind Week 2: Descartes and Dualism

Rene Descartes

  1596-1650 Born in France, travels as a young man to Holland and Germany to serve in the army  In 1618, has a series of dreams that he interprets as telling him he will found a new science

Descartes and Meditation

 Descartes undertakes to

test

all of his opinions to see if they are really knowledge. To do so, he will ask himself if they are based on a

secure

foundation: that is, whether they are certain and immune to doubt.

 He considers various possibilities of doubt or

skeptical scenarios

to see whether he really knows what he thinks he knows

Descartes: Radical Doubt

 Descartes considers three

skeptical scenarios

or possibilities of radical doubt:  1) Senses can be deceptive, for instance when I mistake something far away  2) I could be dreaming  3) God, or an “evil genius,” could be deceiving me by “feeding in” my thoughts and experiences

The Brain in a Vat (a modern version of skepticism)

 If we are brains in vats, we may

think

we are having experiences such as being outside, walking in the sun, feeling the warmth on our faces, etc.

 But we are really just brains wired up to electrical stimulators, perhaps controlled by a computer

Philosophy:

The Matrix

  NEO: This isn’t real?

MORPHEUS: What is real? How do you define ‘real’? If you're talking about your senses, what you feel, taste, smell, or see, then all you're talking about are electrical signals interpreted by your brain.

 How do we know that we are not dreaming?

 How do we know that we are not being deceived by an evil genius more powerful than ourselves?

 How do we know that we are not brains in vats?



IF any of these SKEPTICAL SCENARIOS are TRUE, then what (if anything) might we STILL know and hold on to?

Descartes and Subjectivity: Re-building Knowledge

 “…I have convinced myself that there is absolutely nothing in the world, no sky, no earth, no minds, no bodies. Does it now follow that I too do not exist? No; if I convinced myself of something then I certainly existed… So after considering everything very thoroughly, I must finally conclude that this proposition,

I am, I exist

, is necessarily true whenever it is put forward by me or conceived in my mind.” (p. 10, col. 2)

Descartes and Subjectivity: Re-building knowledge

 Having undertaken to doubt everything he can, Descartes finds that he cannot doubt that he exists as a

thinking thing:

 “I am, then, in the strict sense only a thing that thinks; that is, I am a mind, or intelligence, or reason” (p. 11, 1 st -2 nd column)

Descartes and Subjectivity: Re-building knowledge

 By the end of the Second Meditation, Descartes has discovered that he exists as a

thinking

thing or a

subject

:  “But what then am I? A thing that thinks. What is that? A thing that doubts, understands, affirms, denies, is willing, is unwilling, and also imagines and has sensory perceptions.” (p. 11, second column)

“Seemings:” The Way of Ideas

 “…Lastly, it is also the same ‘I’ who has sensory perceptions, or is aware of bodily things as it were through the senses. For example, I am now seeing light, hearing a noise, feeling heat. But I am asleep, so all this is false. Yet I certainly seem to see, to hear, and to be warmed. This cannot be false; what is called ‘having a sensory perception’ is strictly just this, and in this restricted sense of the term it is simply thinking.” (p. 12, 1 st column)

Descartes and Subjectivity: The Way Of Ideas

  At this stage, Descartes does not know whether anything outside him exists, but he knows that he himself and his own processes of thinking do exist These processes of thinking – the way things seem – can be called “

ideas

.” For instance, Descartes does not know that the sun really exists, but he does know at least that his

idea

or

impression

of the sun does.