The cogito is of an entirely individual application, and one can only conclude one’s own existence from it, not anybody else’s. Nevertheless, we must agree, at this stage, that there is no element of deduction in this process, merely intuitive reasoning. The fact that the cogito can only hold an individual application, and not a general one, serves to prove that nothing is being deduced; the conclusion of the cogito is informed by individual intuition. A third interpretation of the cogito is the ‘performance’ argument.
Its explanation of cogito ergo sum contends that the assertion ‘I do not exist’ is a self-defeating performance, in that the content of the performance contradicts the nature of the performance. In my performance, I am indicating my existence to an audience, thus defeating the assertion ‘I do not exist’. Wilson defends the ‘performance’ argument on the same grounds arguing that following Descartes’ assertion that ‘I exist’, the thought ‘I do not exist’ is an “intrinsically absurd performance”. However, this argument seems largely insufficient.
The interpretation is extremely hard to justify textually as it seems to fail to elucidate Descartes’ central notion of there being an indubitable connection between doubting, thinking and existing. The assertion ‘I do not exist’ can only be self-defeating if it reaches the audience at the time that it is uttered (rather than being read in a book years later), as the intention behind the performance is to draw the audience’s attention to the existence of the performer. And is Descartes’ not concerned with thoughts rather than audible performances?
The major objection to the performance interpretation is the possibility, following Descartes’ earlier assertions, that a demon could be misleading the mediator into being convinced of his own existence; the demon could make the mediator believe that he has proved his existence through attempting to doubt it. Descartes even admits this possibility in the Meditations, when he argues that some propositions that one cannot think of without believing them to be true, may in fact be false.
The incompatibility of the performance argument with the central notion of the cogito providing a link between doubting, thinking and existing precludes us being able to classify the cogito as a performance. Having considered the three arguments, that the cogito is an intuition, a deduction, or a performance, I must conclude that it is an intuition. The deduction argument is fundamentally flawed, particularly as deduction is totally opposed to the method of doubt, in which we must doubt everything but doubt itself.
There is, therefore, no predetermined premise from which we may deduce the cogito. The belief that the cogito is an intuition is the only plausible argument, as its self-evidence – if anyone asserts the proposition, the proposition must be true – remains its defence. I conclude, then, that the cogito is an intuition. I shall now move on to consider whether or not the cogito presupposes anything, and if so whether or not there are any implications. Before considering the existence of any such presuppositions, it would be useful to question the implications.
In order to do this we must look back to the First Meditation so that we might be able to find the basis of the cogito with which any implications might cause contradiction. The essential purpose of the method of doubt is to doubt everything, and in doing so to find a basis of truth. The only thing that we cannot doubt, according to Descartes’, is the intuitive truth that, in doubting, we are proving our existence. So, as long as I am doubting, I exist. The cogito, then, is the product of the method of doubt, as it remains the only indubitable belief.
If the cogito was based upon other beliefs then it would not be self-validating as much as self-destroying. Its very essence depends on there being no other beliefs, and it cannot be based on anything but the intuitive link between doubt and existence. So if one was to find a presupposition upon which the cogito were based, then this would contradict the cogtio’s claim to being the only certain thing. But does this belief that the only certain thing is that I exist when I am doubting not depend on other beliefs? Can we really claim the cogito to be independent of preconceived beliefs, as Descartes, if he were being consistent, would require?
I believe that the cogito does indeed depend on other beliefs. It presupposes knowledge of three central things: what ‘I’ am, and that ‘I’ can know; that doubting is a form of thinking; and that existence is necessary in order to think. Now these three presuppositions may seem entirely fair, and indeed logical. That I do not bring into question. What I do bring into question, though, is the existence of any presuppositions, however valid, in a system of belief based upon the demolition of all presuppositions but one, the cogito.
Lichtenberg raised the objection to the cogito that while Descartes is able to assert with certainty that ‘there are thoughts’, he has no justification for attributing the thoughts to an individual, in the proposition ‘I think’. Thus, he may not conclude ‘I exist’ from this premise, rather he must be satisfied with the weaker conclusion ‘there is a subject of thought’. If Descartes wants to infer the existence of the entity ‘I’, he must find a way to be certain that there is only one ‘I’, a single and continuous identity that is the subject of my thoughts.
Descartes must reconcile ‘I think’ with ‘there is thought’, in order to establish a justifiable base for the cogito on these grounds. Without this he is unable to infer his strong conclusion that ‘I exist’, and must instead rest on the much weaker conclusion that ‘a subject of thought exists’. And although the link between doubting and thinking, may seem perfectly logical, indeed I have no issue with that, only it is a presupposition, which by its very nature contradicts the purpose of the cogito, to be the only certain thing upon which further certain knowledge may be firmly grounded.
And, in a similar vein, the presupposition that existence is necessary in order to think, as ridiculous as it may seem to deny that, still remains a preconceived belief, and thus contravenes the purpose of the cogito. If these presuppositions remain, then we may conclude that the method of doubt has failed to bring every preconceived notion into doubt, and that the cogito, as its product, is contradicted. The only response that I can offer to these arguments is that the presuppositions are not, in fact, presuppositions, but merely intuitions based upon the initial premise.
Some critics, Cottingham among them, also offer in defence that Descartes’ intention behind this project was not to ‘validate reason or to reconstruct the entirety of human cognition from the bottom up’, but the more modest goal of ‘establishing secure foundations for the sciences and showing that it is possible… to achieve systematic knowledge of the world. ‘ I must concede, however, that these responses are insufficient as a defence of the cogito, and while I believe the principle of the cogito to be right, it remains far from indubitable when these presuppositions are in existence.