He initially concentrates upon the sensory beliefs that we hold on a day-to-day basis. He finds the weakest link in the argument, that these are true beliefs, to be the fact that our senses can deceive us. For example, optical illusions, hallucinations and dreams are all times when we think our senses are telling us one thing, when in fact something completely different is occurring. When one looks at a pencil that is submerged in water it appears to be bent when it is actually straight. This illusion is caused because light travels in a straight line continuously and infinitely when travelling through a vacuum, however, when it hits the water it is refracted at an obtuse angle, which creates the effect of a bent pencil.
As a result, Descartes is able to exclude the sensory perceptions as contributors to our infinite knowledge. He then explores other areas of knowledge which have up until now not been questioned for their reliability. He looks at the truths of mathematics. He questions whether every time we add two and three together we get five. This would appear to be a much more difficult subject to tackle, for at no point in time have we added these numbers together after following the applied rules of mathematics and equated any answer other than five. Descartes, however, poses the problem that we could have been deceived all this time by an all-powerful deceiver, namely an evil demon. He claims that this demon could have fixed it so that every time we use our applied rules of mathematics we get a fictitious answer that is consistent through time and place.
And so, the hyperbolic doubt is cast. Descartes has called into question all previously held beliefs obtained via the senses and understood through the previously recognised truths of mathematics. However, although such an argument was ground breaking and unprecedented for its time, this prestige alone will not carry validity to the argument. For it is this very issue of validity that I, the writer and respondent to the above question, intend to divert my attention to. In this case, validity is the ability of the argument to be justified. It is the degree of substance that the argument holds, the weight and authority that it carries.
My first query regards Descartes belief that a thought is caused by something external, namely a more perfect being than that which had the thought. Descartes concludes that this is God. This first criticism of the validity of Descartes argument is posed by one of ‘several men of learning against the preceding meditations’. For he claims that the intellect is not a finite part, it is abstract, 1, “it is simply the determination of an act of the intellect by means of an object”. The comparison is then made between a thought and sight. Just as being seen is nothing other than an act of vision attributable to ones self, so being thought of or having objective being in the intellect is simply a thought of the mind which goes no further than the mind. Therefore if thought is not actual and is a non-entity why should one seek a cause? There need be no cause for that which does not exist.
This conveniently leads me to my second, third and fourth criticism of Descartes’ reasoning. Descartes uses the ‘teleological’ argument to prove God’s existence, who he claims is the creator of the being. It appears that Descartes scrupulously queries all previously held beliefs, finding flaws in all, bar one; God.
1, several men of learning against the preceding meditations, the philosophical writings of Descartes, Cottingham pp 66-72
He claims that God, an omnipotent, omniscient, benevolent, supreme being is perfection personified, if you will. As God is perfection, perfection includes existence and therefore existence is an attribute of God. However, all that this proves is that if God is actual then he must exist. For I could describe to you an island with the whitest sand, the warmest waters, greenest grass and the ripest fruit and yet the
very fact that I can construct a composition with such a refined nature only proves that I have the power of both imagination and aggregate not that such a place truly exists.
Thirdly, Descartes describes God as omnipotent and benevolent. Yet if god was all-powerful and all good why does it continue to let enormous amounts of suffering continue throughout the world. How would Descartes explain natural disasters, such as, earthquakes and the aids epidemic in Africa? Either God was not one hundred percent benevolent or not one hundred percent omnipotent.
Perhaps Descartes belief in God is seriously undermined, although not unequivocally contradicted, as soon as monotheism is added to the equation? The validity of his argument is put into a state of flux as soon as one opens themselves to the mass variety of popular and most common religious beliefs and practices. All of which have their own suitably plausible explanation for their God or Gods as the creator of all that we know today. As a religious man Descartes eliminates himself from introspection. In regards to knowledge, it is undoubtedly a most difficult and arduous challenge to call all that you have previously conceived as true into doubt, but it is implausible to put religion out of ones minds eye. Descartes is naturally biased and apparently religious logical reasoning restricts his enlightenment. For example, Descartes claims that the world has been designed. He draws this conclusion from an analogy between the natural world and the artificially constructed world.
He claims that there must be a creator just as there is for a watch. However, I believe this to be a weak argument from analogy. It takes for granted that there is a significant resemblance between natural objects and objects which we know to have been designed, the eye and the watch for example. Although there is some similarity between the eye and the watch i.e. they are both intricate and fulfil their own individual functions, it is only a vague similarity and any conclusions based on the analogy will, as a result, be correspondingly vague. A counter argument, which I find more plausible, is that by Charles Darwin, the theory of evolution by natural selection, illustrated in his book ‘The origin of species’.
If the line of argument, cogito ergo sum is adopted and to be more direct and less discreet one was to say I am thought itself, I am a mind, then to follow Descartes’ scientific inductive cause and effect analysis then either the mind is self creating or it is created by something external. Now, the arguments for god as the creator, some of which are elaborated on above apply also to the argument that the mind may have been self-creating. Why, if the mind was self-creating, did it not endow itself with the greatest of mind powers, such as, that of memory or imagination? If the mind was self-creating then it would have surely evolved over time as it arguably still is. This suitably returns us to Darwin’s evolution theory.
To conclude, the Cogito argument, is in my opinion, valid. The logic follows on in a justified and necessary manner. I was unable to question the statement ‘cogito ergo sum’. The very fact that I have the ability to question whether I am thinking eliminates, for me, the chance of deception by a higher order being, an evil demon or otherwise. I am, at least for now, quite happy and eternally optimistic that Descartes is right about our perception of what is and what is not epistemologically accountable. Whether I deceive or convince myself that Descartes is correct because of my will and need for an existence of some reality I am unsure. Perhaps a truly unbiased answer to the question above regarding the validity of the cogito could only come from a being or otherwise that consists of post mortem existence. However, although I am prepared to resign to Descartes conclusion that we exist at least as a thinking being, I am not prepared to agree with him on any level that we were designed by an all powerful, all good, all knowing deity. Strong criticisms, such as, the monotheism argument, the theory of evolution and natural disasters all hold a strong justified position as critiques of God as the all mighty creator. Nonetheless, I now realise what a massive overhaul this 17th century thinking must have been and recognise that whether valid or otherwise this certainly acted as a catalyst for philosophical thought in regards to the mind and body debate.
