It took Descartes a long time before he realized how many false beliefs and assumptions he had from his childhood. To start over with a new mind set, he had to totally rid himself of assuming things been true or things that he had not questioned but had rather accepted as a truth. Descartes waited for a when he was retired to come up with his opinions and question the truths. He therefore had plenty of time to ponder and really nothing to loose in terms of leisure, care and passion. What Descartes first meditation starts out to do is not to base or accept as the most true certain things his senses had made him accept as true.
For example, if Descartes saw a piece of wood when he was younger he would have automatically assumed or believed it came from a tree. This was his automatic assumption because this was what had been instilled in his thought process which was that wooden objects came from trees. This is what we could call the perception of our senses. Our senses take the front seat of our thought and we hardly ever question it. Not basing his beliefs on his sight would satisfy not trusting a deceptive sense such as sight as used in our example because of its deceptiveness to come to a true belief..
Descartes slowly moves on to set the stage on another argument which I shall call the dreaming argument. The dreaming argument is centered around differentiating our awakened mind from sleep. Descartes uses this technique and builds upon it to show that an external world doesnt exist. Descartes makes a good argument by using scenarios which happen to everyone whilst having a dream. Descartes believes that our dreams usually represent unclear settings of ourselves and while not in a dreamy moment ourselves we can’ be very clear if what we experience while awake really are occurring.
Simply put, reality and when we are in a dreaming state is so blurred that sometimes or most times when we have dreams we tend to think we arent dreaming but are actually experiencing a real situation. Descartes hammers his point here by saying that if we cant clearly differentiate from the onset reality from a dream clearly and accurately then can we truly make a distinction between our world and an external world. Even more does an external world exist? To Descartes the external world may be an assumption or illusion of our present world with a lot of figments of our imagination put there.
Descartes method of doubt is all derived from the assumption that everything we already know or have come to know as been true are false. He goes as far as basing his doubt on not trusting our senses since from birth they have always been deceiving us. The skeptical arguments in Descartes first meditation are the clarity of our perceptions as used in his example on the sciences. I agree wholly in this argument. Most sciences that build upon asserting their existence are easy to disprove. On sciences such as physics, astronomy and medicine.
I for one have taking a lot of physics classes and have often thought of why it all had to start with assumptions. Taking Descartes side I cant prove most of what I assume to be true but it is really easy to doubt them and disprove them in a plain sense. Other sciences such as mathematics dont bring along assumptions but proofs. As Descartes puts it, sciences such as mathematics are very simple and direct at bringing a point. It is thus very hard to disprove a theorem or calculation because mathematical theorems and proofs are built upon factual reasoning.
The dreaming argument is another in which with every experience in the dreams occurring we cant be sure if we are dreaming or awake and therefore we dont know if anything occurring is true or false. His third and last skeptical argument is the evil demon concept. He brings about the evil demon argument to attempt to show that the universe consists of me and an all powerful being which we have come to know as GOD has infinite powers to make us have false beliefs of various aspects of our lives. On Descartes saying we dont know there is an external world, I disagree very much