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13. Knowledge Criteria / D. Scepticism / 5. Dream Scepticism

[apparent reality may be just a false dream]

7 ideas
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)
Dreams aren't a serious problem. No one starts walking round Athens next morning, having dreamt that they were there! [Aristotle]
     Full Idea: Is it really an issue whether things are true that appear to those asleep or to those awake? No one in Libya who dreamt he was in Athens, would set out for the Odeon next morning!
     From: Aristotle (Metaphysics [c.324 BCE], 1010b09)
You know you were dreaming when you wake, but there might then be a greater awakening from that [Zhuangzi (Chuang Tzu)]
     Full Idea: Often after waking do you know that your dream was a dream. Still, there may be an even greater awakening after which you will know that this, too, was just a greater dream.
     From: Zhuangzi (Chuang Tzu) (The Book of Chuang Tzu [c.329 BCE], 02), quoted by Bryan van Norden - Intro to Classical Chinese Philosophy 9.2
     A reaction: This is the key to the full horror of dream scepticism (as dramatised in the film 'The Matrix'). We can never know whether there is yet another awakening about to occur.
Did Chuang Tzu dream he was a butterfly, or a butterfly dream he was Chuang Tzu? [Zhuangzi (Chuang Tzu)]
     Full Idea: Once I, Chuang Tzu, dreamt that I was a butterfly, flitting around and enjoying myself. Suddenly I woke and was Chuang Tzu again. But had I been Chuang Tzu dreaming I was a butterfly, or a butterfly dreaming I was now Chuang Tzu?
     From: Zhuangzi (Chuang Tzu) (The Book of Chuang Tzu [c.329 BCE], Ch.2)
     A reaction: Plato (Idea 2047) also spotted this problem, later made famous by Descartes (Idea 2250). Given the size of a butterfly's brain, this suggests that Chuang Tzu was a dualist. What can't I take the idea seriously, when reason says I should?
Waking actions are joined by memory to all our other actions, unlike actions of which we dream [Descartes]
     Full Idea: Dreams are never joined by the memory with all the actions of life, as is the case with those actions that occur when one is awake.
     From: René Descartes (Meditations [1641], §6.89)
Dreams must be false because they seem absurd, but dreams don't see waking as absurd [Hobbes]
     Full Idea: Because waking I often observe the absurdity of dreams, but never dream of the absurdity of my waking thoughts, I am well satisfied that, being awake, I know I dream not, though when I dream I think myself awake.
     From: Thomas Hobbes (Leviathan [1651], 1.02)
Dreams can be explained fairly scientifically if we assume a physical world [Russell]
     Full Idea: Dreams are more or less suggested by what we call waking life, and are capable of being more or less accounted for on scientific principles if we assume that there really is a physical world.
     From: Bertrand Russell (Problems of Philosophy [1912], Ch. 2)
     A reaction: This sounds a bit circular, since scientific principles depend entirely on the assumption that there is a physical world. No doubt if we assume fairies, 'fairy lore' will explain everything. 'Explanation' is the basic concept here.