| Doubting the senses . Descartes begins by pointing out that our senses are unreliable . So, we can doubt that what our senses tell us is accurate and so they cannot be the foundation |
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| Doubting the physical world I have seen tables in my dreams, I could be dreaming of it. Evil genius is determined to deceive you into thinking that there is a physical world when there isn’t one |
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Doubting Mathematics
Descartes thinks that he can imagine a scenario in which 1 + 1 does not equal 2
evil genius is tricking me into thinking that 1+1=2