Descartes on the Cogito

The Cogito

- In such a state of doubt, the one thing that I cannot doubt is that I am in fact doubting right now.

- Doubting is a form of thinking

- So, I know that I am thinking, even if the thing I'm thinking is 'I'm so confused! I don't know anything any more!'

? ? If I'm thinking then surely I must exist. I must be real if I'm able to think. I might not know what I am, or whether this body that I think I inhabit is really here, but I do know that I am here thinking.

- So, famously, this leads Descartes to pronoun cogito ergo sum, 'I think therefore I am'.

Cogito ergo sum

- In the Meditations, he says 'I am, I exist'

- In the Second Replies, he writes 'I think, therefore I am, or I exist'

What is the Cogito?

- Is this:

? ? 1. An argument? - I think; [whatever thinks exists;] therefore, I exist (it 'follows' that I exist). Formally: A, if A then B, therefore B.

? ? 2. An intuition? - I simply know, when thinking, that I exist (it is 'most evident').

? ? 3. A necessary condition? - In order for me to be able to think, I must exist (it is 'necessarily ture').

- Or is perhaps more than one of these at the same time, all of them, or indeed none?

Descartes' Answer

- In the 2nd Replies, although he presents it in the form of a syllogism, he denies that it is an argument. Instead he describes as an intuition, and as a necessary condition:

A thinking thing

- In the course of this discussion in the 2nd Meditation Descartes describes himself as a 'thinking thing' (res cogitans)

- In the 5th Replies, he glosses this by saying that he is a thinking substance (substantia cogitans)

- Is he justified in making those claims?

????????I am thinking, I am -> I am a thing that thinks [what is a 'thing']

????????I am thinking, I am -> I am a substance that thinks [what is a 'substance']

Georg Lichtenberg's Objection

- Descartes does not prove the existence of a thinking substance or thing, nor even the existence of 'I', a conscious entity. All he proves is that there is thinking happening, not that I think.

- Should Descartes merely say 'there is thinking taking place'?

Stressing 'I'

- But Descartes stresses I with his use of ego. It is I who thinks. His phrase ego cogito is far more emphatic than just cogito (which on its own means 'I think')

- See also the 3rd Replies to Thomas Hobbes:

Something Paradoxical

- The thing that is beyond doubt, 'I' a thinking thing, has a nature completely unknown to us.

- By contrast, bodies, whose existence can be doubted, seem on the face of it much better?known: solid, three-dimensionally extended, etc.

The Nature of Bodies: The Piece of Wax

- We apprehend a piece of wax via the senses (taste, smell, sight, touch).

- When heated, all its most obvious properties change (smell, colour, shape).

- What stays the same? What is the essential nature of the was? Extension.

- Its essential nature, extension, is grasped not via the senses, but by the mind.

Implications

- It is with the mind, not the senses, that we comprehend bodies.

- Knowledge is the product of understanding, not perception (rationalism, not empiricism).

- Perhaps this might give a clue to how to comprehend the nature of myself, a thinking thing - i.e. through further rational reflection.

Some Conclusions

- I am a 'thinking thing', but what type of thing that is remains indeterminate. Definitely some kind of thing, because all acts require a subject, but it is not clear whether material or immaterial at this stage.

- Bodies are essentially extended things (res extensa), and we know this via our understanding, not perception.

- Implicitly, then, there is a contrast between thinking things (res cogitans) and extended things (res extensa), but we shall have to wait until the 6th Meditation for this to be made explicit.

- On his journey so far, Descartes has douted all his pre-existing beliefs. The only thing he knows for sure is that he exists, but all he can say about himself is that he is a thing that thinks. It's on the basis of that small foundation that he wants to rebuild the entire edifice of human knowledge.

Questions

Read the 2nd Meditation and think about these questions:

- Is the Cogito an argument, an intuition, or a necessary conditon?

- What, if anything, does Descartes prove to exist with the Cogito?

- What does Descartes seek to demonstarte with the example of the piece of was?