Philosophy – Can Descartes Be Certain He Is Thinking
Can Descartes be certain that he is thinking? How? Can he be certain that he exists? How? (And who is he?)
Descartes statement I think therefore I exist raises questions about the meaning of thought, the meaning of existence but most fundamentally, in what sense he can be certain. The difficulty in establishing the certainty of I think and I exist is that the two concepts are interrelated. Thus, for example, differing interpretations of what it is to think will have a profound impact on the question of whether Descartes can achieve the certainty of his existence. The success of his attempt to achieve certainty can be analysed in relation to how far he overcomes the universal doubt he has introduced in the first meditation. It is in this sphere of meaning that I becomes very relevant as it is possible to argue that his use of I demonstrates that his own interpretation of what is certain is partially based on intrinsically held beliefs.
Williams describes the statement I think as indubitable. This is because if anyone believes he is thinking or that he exists then necessarily he has a true belief. Using the Cartesian method, the statement that I think is unique because it is the only premise that has the property of having its truth confirmed by the act of doubting it. Descartes demonstrates that he has found a statement that is not defeated by the possibility of a malicious demon when he says If I am in doubt, if I am entertaining the possibility that I might be deceived, then the very fact that I am around to entertain that doubt shows that I must exist. Thus he is already assuming that his ability to entertain doubt, or think is certain, which based on the premise above, is a not unreasonable conclusion.
Before further examining his assertion that he is thinking, the question of what Descartes means by thinking must be defined. In the simplest form, possible definitions of what it is to think can be separated into wide and narrow definitions. In the second meditation, he appears to define thinking in terms of all conscious acts when he describes a thing that thinks as a thing that doubts, understands, affirms, denies, is willing, is unwilling and also imagines and has sensory perceptions. Williams makes the point that the translation of the Latin verb cogitare and the French verb penser have wider meaning than the English to think. They relate to any conscious state or activity. However, if Descartes definition of thought was really this broad it would need to be possible to assert that having sensory perceptions was indubitable as the ability to think. However, as he asserts in the first meditation, it is not the case to believe that I have sensory perceptions necessarily makes it a true belief. Despite this difficulty, Descartes inclusion of, among others, imagination in the above definition of thinking demonstrates that he clearly does not interpret thinking in the narrow sense of being just a cognitive act of the intellectual kind. However, as Cottingham shows, this is partially the fault of categorising the definitions of what it is to think to rigidly. When Descartes says that it is necessary to doubt, understand etc. he is actually referring to the ability to be aware of these rather than being able to control the activities in their own right. Thus the assertion that I am aware that I have sensory perceptions is as indubitable as I am aware that and is thus equated with I think. Williams describes this as Descartes willingness to sheer off purely mental experience. Thus the conclusion can be reached that thought can be defined as that of which I am immediately aware.
To return to the question of how he can be certain that he has a true belief, Williams writes that Descartes certainty that he thinks is based not just on its incorrigibility, but also on its self verifying nature. If Descartes asserts I think then this must be true because the act of thinking the statement, proves it. Of course, I think is the only concept that can be self verified thinking I exist does not make it true.
Prioritising the importance of the relationship between I think and I exist is where Hintikkas performative interpretation becomes relevant. This interpretation states that the very act of thinking makes it true. Therefore an argument for the certainty of I think is that Descartes himself has made it true. However, it can also be claimed that this leads to the question of whether it is important that Descartes is certain that he thinks. The very act of thinking means that he is doing it and therefore consideration of whether he is certain he is thinking or not may be deemed redundant in a particularly pure interpretation of the cogito. In contrast, I exist is not performative and thus it is I exist that needs to be established as certain. In a roundabout way, the performative interpretation brings the same result as the self-verifying interpretation of the cogito. This line of argument leads to the question of whether I think is necessary as a reflexive proposition at all, or rather is only important as the process by which it is possible to become aware of the certainty of I exist
If it is argued that thinking is not the just the process of recognising I exist to be indubitable but rather, that being able to establish I think as indubitable provides grounds for concluding I exist, than it is necessary to describe what these grounds are. Thus if this is the purpose of I think then the implication is that is it possible to infer I exist from I think. Thus commentators on Descartes such as Burnham have tried to establish whether the cogito can be said to be a Syllogistic inference. It has been argued that Descartes provides the minor premise I am thinking and the conclusion I exist and therefore it is possible to define the major premise as whatever is thinking, exists, demonstrating a syllogistic inference. This claim would appear to be supported by the use of therefore in the cogito, which does imply an inference.
However, Descartes himself expresses this interpretation as a profound misunderstanding of his point. Firstly this argument fails on the basis of his inability to have previous knowledge of the major premise whatever is thinking, exists. In his reply to the Second Objection, Descartes states this point and adds that when someone says I am thinking, therefore I am, or exist, he does not deduce existence from thought by means of a syllogism but recognises it as something self evident from a simple intuition of the mind. His point is that the conclusion he has reached is based of what is self-evident from what he has perceived in himself. However, Williams insists that his should not be interpreted as a purely psychological point that the experience of grasping the Cogito is that of an instantaneous insight. According to Williams, Descartes does believe that there is a link between thinking and existing. However, rather than assert Everything that thinks, exists, he asserts It is impossible to think without existing, the difference being that this alternative expression of the link can be intuitively grasped as it does not relate to the outside world. It makes sense that Descartes is unable to make his existential claim that everything that thinks, exists on the basis that he cannot presuppose things to be in existence. Thus one interpretation of the use of I in the cogito is that it is a demonstration of the fact that his conclusions are based on what he has perceived within himself, not externally.
In opposition to this interpretation of the use of I, Lichtenberg claimed that the most Descartes could claim was that there is thinking going on. In fact what Lichtenberg criticises is exactly the fact that Descartes conclusions are based on what he has perceived and not the objective case of an outside observer. He is claiming that Descartes has not basis to assume that there is a thinker as opposed to thoughts going on. There are two responses to this interpretation of the use of I. Firstly that the I is a replacement for here in terms of providing a necessary sphere in which two thoughts such as I think and I exist can be related to each other. However, this argument would not actually enable Descartes to make the connection between I think and I exist in the way that he has claimed to as the I would purely be a means for relating the concepts and thus Descartes would have no way of perceiving things in himself. A more consistent reply is that the concept of an outside observer is not possible within Cartesian reflection because the only way of conceiving a thought happening is to conceive of thinking it.
In the terms of the above argument, Descartes claim that his conclusions are based on self-evident intuition is consistent with his method of doubt. However, in terms of this same Cartesian method, there appears to be a fundamental problem with the claim that Descartes can be certain that he exists. He claims that he bases his conclusions on instincts that he calls natural light and are therefore presupposed. A fundamental example is his belief in the intuitive grasping of the link between thinking and existing. In discourse four, he expresses this when he says that there is nothing that assures him he is speaking the truth other than conceiving very clearly and very distinctly. Thus Descartes is unable to claim to become certain of his own existence on the basis of the method of doubt expressed in the first meditation. He is forced to rely upon (if naturally intuitive) presuppositions in terms of being certain of his own being.
