What is thread 1?
Rationalism Descartes Intuition + Deduction Cogito->God->EW
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The Cogito
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Cogito cannot be justified
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so cogito is wrong, but if it wasn’t he would be wrong on God.
What is thread 2?
Descartes ontological argument
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Existence claims are a posteriori and contingent
What is thread 3?
Cosmological argument
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Relies on causal principle which cannot be justified a priori
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So he is wrong on God too, but if he wasn’t he would be wrong on the external world too.
What is thread 4?
Proof of the external world
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Dreams and illusions still lead us to scepticism