However, he was not able to judge which type each and every thought corresponded to; he had the natural belief that sense experience is adventitious, that is, caused by the external, however, this was only a belief, and so he felt he must be cautious, as he could not know for sure. Another ambiguity he identified was that of his idea of the sun, or that is, his two ideas of the sun. He has one idea of the sun being a very small object that was can see in our sky, and another idea which is an astronomical reflection of it as being very large. He concludes that he is unable to decide which is the correct one, and that both could very easily be fictitious.
So he then goes on to consider his ideas from two different perspectives: as ideas in his mind, all on one level, and equivalent to each other. And in the difference in what they possess or represent, this being the content of those ideas. These two can be defined as the formal reality of the idea, that is, the reality in the thing itself, and the objective reality, which is the reality in the content of the idea. Descartes then goes on to use some old scholastic assumptions, which he feels are so self evident they require no justification, which everything else up to this point seems to have needed. He reasons that everything has a cause, and that the cause of something must have as least as much reality (perfection) as the effect; the causal adequacy principle as Cottingham named it. This must mean the cause of an idea I have is in fact greater than the objective reality this idea possesses; the cause has eminent reality.
Descartes finds that this holds true for all the ideas he possesses. The only slight ambiguity he finds is that with the idea of God. Descartes believe that the idea of god is innate, that is, of a completely perfect being. He argues that the idea could not have come from sense experience, as the idea transcends anything we as finite beings are able to create, and that he could not have created the idea in his imagination for the very same reason; that even by multiplying one quality many, many times, you can still never reach the infinitesimal attributes that his idea of God possesses. Descartes thus concluded that his idea of God is a very special one; if he did not himself create the idea, where did it come from? He looks to his parents, maybe he inherited the idea off them; but if he did, this must mean they are the cause of the idea, and so possesses more reality than the idea. Because the idea is that of a perfect being, his parents must have greater objective reality than that of a perfect being; but being finite, they clearly don’t. So he concludes that the idea must have come from somewhere else; it must have been implanted in him by something that has greater objective reality than the actual idea. So from an objective appraisal of the idea Descartes possesses, he is able to conclude that God is the cause of the idea of God; that is, it is God who has implanted this idea into Descartes mind; its totally innate and can be seen as a mark of the marker on his work. This is why the argument is known as the ‘Trademark’ argument.
There have been many criticisms of the argument Descartes offered; the main objection coming from his use of scholastic assumptions. In his first Meditation, Descartes says that he will steer clear o former opinions and begin afresh, and yet here he returns back to the old ideas of cause and affect. Using this principle he makes three assumptions: that cause is a priori, that is, that all events are in fact cause, that whatever causes and event must be equal to or greater than its effects, and that something cannot be created from nothing. He does not address these issues at all, and many philosophers may consider them contentious, including Hume. He doubted the very reality of cause and effect, and said that it is not in the universe, or himself at all; it is merely something we impose on individual events. He also sys that the idea of God is a human creation based on all the goods he has seen multiplied many times.
May people also contest that they do not even have an idea of God in their minds. Although Descartes responded to this by saying that if we do use the word God, then we must in fact have the idea of him. However, Gassendi said that even if we used the word God, it does not prove that we have an idea of an infinite being. It could merely be an evil daemon, something greater than Descartes.
Another point to consider is whether or not a finite mind can even comprehend the infinite. Does it make sense? Descartes would probably respond to this by saying that whilst we have the idea of infinity/perfection, we do not fully understand it.
Taking another look at Descartes scholastic assumptions that there must have been a first cause to everything is in itself a contradiction. If all things have a cause, how can there be a first cause? There could viably be an infinite regress of causes; if Descartes would reject this idea of infinity, similarly you could reject the idea of an infinite God. Why do things even require a cause? Why can they not simply be there, as a brute fact, or some about by accident?
I feel that the main problem is that Descartes has set out to prove the existence of God, and has therefore been working backwards from the premise that he must exist. This has led him to take on old scholastic assumptions that can be doubted, and a shaky foundation is not what he needs. He claims that its certain by ‘the light of reason’, but what may seem totally indubitable to Descartes may be considered less so by others who are not as blinded by the need to prove the existence of a God. He does not even address the possibility that these ideas of cause and effect could be the work of the evil demon. This leaves Descartes ‘proof’ for god looking very uncertain at best, and so the way in which he uses God to justify the existence of external objects is fundamentally flawed. This means he is left with a belief that he is existing along with a God that’s not totally certain, and so living in a world that probably doesn’t even exist.
