Descartes: A Biography

c CUNYB/Clarke     December, :

 Descartes: A Biography

the sceptics were unable to shake it, I judged that I could accept it without

scruple as the first principle of the philosophy for which I was searching’

(vi.). Of course, Silhon was neither the first nor the most famous

exponent of this argument. It is found as early as Aristotle, and more

famously in Saint Augustine.When Andreas Colvius (–), a

friend of Beeckman at Dordrecht, pointed out the similarity to Augustine’s

argument inThe City of God(xi.), Descartes consulted the book in the

university library at Leiden and replied:

Iamobliged to you for alerting me to the passage in Saint Augustine with which my

‘I think, therefore I exist’ is somewhat similar....I find that he used it to prove our

existence, and then to show that there is an image of the Trinity within us insofar as

weexist, we know that we exist, and we love this being and this knowledge within us.

However, I use it to show that thisIwhich thinks is animmaterial substanceand that

there is nothing corporeal about it. These are two very different things. (iii.)

Descartes’ correspondence about the similarities to St. Augustine imply

that he was not familiar with Augustine’s work and that he did not borrow

the argument directly from this source.Of course, he may have been

dissembling again and exaggerating the novelty of his argument.

According to their subtitle, theMeditationswere written to demonstrate

that the human mind is distinct from the body and that God exists.

Descartes aimed for the first conclusion by showing that the activity of

thinking cannot be explained in terms of the properties of matter.He

could not produce an argument to show that mental activity cannot result

from some complex activity of the brain and the senses. His task was more

modest and feasible: to examine the evidence that supports what we would

today call a scientific explanation of mental activity. He concluded that we

might eventually discover that, in human beings, ‘there is one nature that

is both intellectual and corporeal’, but it was impossible into explain

mental activity in terms of bodily events.As long as this gap obtained

in our theory between mental events and what we know about physical

events – as it still does – Descartes thought that the only intellectually

honest conclusion to draw was that mental properties are distinct from

physical properties. There was thus a residual dualism in the incomplete

Cartesian theory of human beings. However, Descartes was not proposing

dualism as a successful theory. He was not arguing that we couldexplain

thought by attributing a ‘thinking faculty’ to human beings. That would

have been as uninformative as explaining how sleeping pills work by saying