he 'cogito' argument (from 'cogito ergo sum'; I think therefore I am.).
             Hence, according to Descartes, we can now say 'I know something'; that I exist. In addition, we can say that the 'cogito' proves the existence of a criterion of truth; as such a thing is implied by any certain knowledge. Yet Descartes does not feel that this is all that we can know. After proving our existence (as thinking beings at least), he goes on to 'prove' the existence of a God, via two methods. In Meditation three, Descartes uses what has become known as the 'Trademark Argument'. The argument is as follows:
             1) I have an idea of God, as a Being with all perfections.
             3) All ideas are either innate, sensory or artificial.
             4) The idea of God is not sensory or artificial.
             5) The only thing that can cause the idea of God is God.
             In Meditation five, Descartes uses an 'a priori' argument called the 'Ontological Argum
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