It is necesary to discard everything and start from the foundation ,if he is to establish any truth
I must make an efort to remeber what i've discovered in this meditation
I will therefore deceive myself and pretend that all my former beliefs are false to counterbalance my bias
I will suposed that there is no god instead there is a demon who's main goal is to decieve me
I shall consider everything around me as a delusion made to harm my judgement
I shall firmly persist in this meditation and guard agaisnt all falsehoods.
If god is supremely good it would be contrary to his goodness to create me in such a way to be deceived all the time
If god is supremely good it would be contrary to his goodnes to allow me to be deceived even sometimes
I know God allows me to be deceived sometimes
There are never any sure signs to differentiate being awake or dreaming
Fiction is at least in the very simplest way based on reality
If I am dreaming then my dreams must be based on some sort of reality
Therefore even if I am dreaming these basic universal truths are true
Corporeal nature, numbers, space of objects( in theory) can be taken as true
Arithmetic, geometry and other simple things, which deal with things regardless of wether they exist in nature ( which we can't prove yet) are certain.
Therefore physics, astronomy medicine and all things that rely on complex things are doubtful
I often experience similar or even more improbable events as the madmen when I dream
I sometimes have dreams of mundane life
On occasion I have believed I was awake when I was really dreaming
Descartes' First Meditation
If there is no God then I came about through a random series of events
since deception and error are imperfections it seems more likely that I am deceived all the time
There is not one of my former beliefs that I have no doubt in
I must distrust all my former beliefs in the same way I would falsehoods
I believe that there is an omnipotent god who created me
It is possible that there is no world in the way I see it but that he has made it so it appears as such to me
If something is not certain it
is as invalid as something that is false
To reject an opinion I only need to establish doubt
Most of what I believe is based on my senses
My senses have fooled me before and so I cannot trust them completely
There are many things that we think it impossible for our senses to deceive us in
Madmen are equally as certain of certain things that we know are false
I think I am not mad
There are many falsehoods
I accepted as true in childhood
The edifice of knowledge based on
them is highly doubtful
It is necesary to discard everything and start from the foundation,if I am to establish any truth