Combining Texts

Ideas for 'Theaetetus', 'Academica' and 'Gentzen's Analysis of First-Order Proofs'

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2 ideas

13. Knowledge Criteria / D. Scepticism / 3. Illusion Scepticism
Every true presentation can have a false one of the same quality [Cicero]
     Full Idea: [The sceptical Academics say] what is false cannot be perceived, but every true presentation is such that there can be a false presentation of the same quality.
     From: M. Tullius Cicero (Academica [c.45 BCE], II.40)
     A reaction: It was the stoics who focused the discussion on 'presentations'. This claim is purely theoretical; no one has ever experienced a false presentation of talking to a family member that was as vivid as the real thing.
13. Knowledge Criteria / D. Scepticism / 5. Dream Scepticism
What evidence can be brought to show whether we are dreaming or not? [Plato]
     Full Idea: What evidence could be brought if we were asked at this very moment whether we are asleep and are dreaming all our thoughts?
     From: Plato (Theaetetus [c.368 BCE], 158b)