1. The Role of God in the Meditations (1) Context
Trying to refute scepticism Descartes becomes an ultra sceptic as a method of refuting scepticism.
Using arguments from illusion, dreaming and evil demon Descartes has undermined all sensory and mental knowledge – a priori and a posteriori paths to certainty.
Finds his foundation point in the Cogito.
Establishes the principle that whatever is clear and distinct is reliable.
But since Descartes is still in the position of being in the grip of the evil demon how is he to establish that the clear and distinct rule is trustworthy and proceed to rebuild the house of knowledge?
To do this he needs God and proceed to try to prove the existence of God in Med 3.
But this must be an a priori proof!

2. The Role of God in the Meditations (2) The Trademark Argument
There is an idea of perfection in the mind. This is an innate idea.
Descartes accepts the causal adequacy principle. The origin of something must at least be the equal of what it causes. Effect cannot be greater than the cause.
Humans cannot be the cause of the idea of the perfect God because we are not perfect. Descartes notes his many imperfections – and ours!
Nothing else in nature has the concept of perfection so nothing else can account for the presence of the idea of a perfect God except a perfect God.
The a priori concept of a perfect god in our minds has been placed there almost like our creator’s stamp upon us – his trademark.
Thus the concept of God is proof of his existence.

3. The Role of God in the Meditations.(3) God’s Guarantee.
Having “proved” God’s existence Descartes has taken a major step towards rebuilding our knowledge on certain foundations.
Descartes assumes God is not merely a “first cause” but the omnipotent, omniscient and good God of the Christian tradition.
Thus “God is no deceiver” – God is totally good after all!
So such a God will be greater than the evil demon whose power is now seen to be broken – being omnipotent and good Descartes’ God would not allow the evil demon to deceive.
So God guarantees clear & distinct perception, sense experience and is foundational for knowledge.
Reality & perception of it are resting upon God.

4. The Role of God in the Meditations (4) Criticisms
The Cartesian Circle. Descartes needs God to guarantee the clear and distinct rule – but God is one of the clear and distinct perceptions! Catch 22!
The idea of perfection may have little meaning outside Maths. Do we have a concept of perfection in our minds at all, let alone a perfect God?
God is invoked as a matter of desperation and convenience for Descartes just as God was invoked at the end of a messy Greek play to tidy the plot up – Deus ex Machina.
Descartes is now accepting things his own method as outlined in Med 1 would never allow.
Descartes merely assumes a God who is good but does nothing to prove such a God

5. Role of God in the Meditations (5) Criticisms
Causal Adequacy Principle. This is contradicted by experience of evolution. Evolution shows clearly that the greater arises from the lesser – more complex species have their origin in simpler creatures.
If we could conceive of a perfect island or perfect body would it have to exist just because we can think of “perfection” without actually seeing it in life?
If God is good – no deceiver – why am I still seriously wrong about some things sometimes – if I can be deceived once – why is God no deceiver?
If God is good then why is there evil and suffering in the world? The old problem of evil. Descartes claims goodness and omnipotence for God but the evidence points to a God who cannot be both. A good God would want to stop pain – a powerful God could stop pain.

6. The Role of God in the Meditations (6) Conclusions.
Descartes knows he is dependant upon God. Cannot get out of solipsistic position without God.
God is pivotal and foundational.
God more important as a foundation than Cogito?
Trademark Argument fails.
Therefore reality and human perception of it is not shown to be certain.
Descartes has not been successful in solving the problems of Med 1. Failing to prove the existence of God and failing to establish the nature of God as good and omnipotent mean the Cogito is the only credible certainty but without God being proven this is a dead end.