What’s wrong with the cogito?
1) Is there a questionable hidden premise?
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Most criticism is of the cogito in its earlier format:
“I think therefore I am”, in the Discourse on
Method.
1) The hidden premise:
(First raised by Lichtenberg)
I think
Thinking things exist
Therefore I am
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What’s wrong with the cogito?
1) Is there a questionable hidden premise?
The hidden premise:
I think
Thinking things exist
Therefore I exist
This premise is questionable -Does the existence of thoughts
necessarily imply a thinker? David Hume argued that we have no
right to assume this, as does the anatta (no-self) doctrine of
Buddhism. Perhaps Descartes should have said, “There is
thinking going on; therefore there are thoughts.” The cogito
therefore doesn’t actually establish the existence of a self.
“I” is merely a linguistic convenience. It doesn’t actually refer to
anything, any more than the “It” in “It is raining.”
Descartes strays from his rationalistic agenda here since
“thinking things exist” is an a posteriori, empirical observation.
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What’s wrong with the cogito?
1) Is there a questionable hidden premise?
The hidden premise: counter arguments
I think
Thinking things exist
Therefore I exist
Ownerless, thinkerless thoughts – pretty weird!
The suppressed premise argument assumes that Descartes intended the
cogito as a piece of syllogistic (deductive) logic. However, Descartes did
not intend the cogito to operate this way. The Meditations should be
seen as a course in guided self-discovery and the cogito as a selfauthenticating proposition. According to Cottingham, Descartes
expressly made this point to Leibniz at the time.
Descartes restates the cogito in the Meditations as “I exist is necessarily
true.” to clarify this and overcome the criticism
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What’s wrong with the cogito?
2) The cogito is circular.
I think
Therefore I am
According to
Bertrand Russell
the cogito is
circular since it
assumes what it
is setting out to
prove.
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What’s wrong with the cogito?
2) The cogito is circular. Counter argument
I think
Therefore I am
But as with the hidden premise
argument, Descartes never intended
the cogito to be a deductive
argument, and his restatement of the
cogito in the Meditations (I am, I
exist is necessarily true) overcomes
this criticism.
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What’s wrong with the cogito?
3) The cogito is trivial - It doesn’t tell us anything of significance.
Most critics of Descartes are willing to grant
him the cogito, but would argue that if this is
as far as his argument goes then he has
established very little indeed. His task is to
overcome scepticism and produce some
certainty about the world out there.
He claims this is his Archimedian point, his
foundational proposition upon which he will
build knowledge but, as we shall see, he
abandons this as a foundation, and uses
arguments for God as his means of
overcoming scepticism.
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What’s wrong with the cogito?
4) Could you exist without a body?
Descartes is a dualist - he believes in the existence
of a body and a mind. He argues that although he
may be deceived by an evil demon into believing he
has a body, he must have a mind since he has
thoughts.
This viewpoint is contrary to modern neuro-science
(study of the brain) which takes a monist position –
we only have a body. Thoughts exist in the brain
nerve cells. Without a brain there can be no
thoughts. If you can’t exist without a body then
Descartes’ position is seriously undermined.
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What’s wrong with the cogito?
4) Could you exist without a body? Counter argument
Descartes argues that he has more
certainty of the existence of the mind
than that of the body because, whereas
he may be deceived into believing that a
physical world (including his body) exists,
he, as a mind, must exist to be deceived in
the first place.
He says that although he can’t establish
that he has a body, he can establish that
he is a “thinking thing”.
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