Quote:
Original post by superpig
Try it this way: "If I cease to have direct sensory experiences of a thing, how do I know that it still exists?"
Or further, because you can't trust your sensory input: "How do I know that anything other than me really exists, and that I'm not just living in the matrix?"
Or solipsism: "How do I know that anyone other than me is conscious, instead of it just being my imagination that they are?"
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Quote:
Its like saying "I baked a cake. Did I bake a cake?"
This one's a little more fun if you rephrase it as "I have memories of baking a cake. Did I bake a cake?"
I would say that it makes sense to seriously think about these questions as an intellectual exercise. However, they quickly devolve into useless playing with words, and are ultimately trivial or irrelevant. The interesting part is *that* they're irrelevant, and how and why.
For example, the last question about memories. Obviously it is possible that you didn't bake the cake and that instead somebody fabricated a 30 second old universe containing everything we know, including you with your memories of baking a cake.
However, this would change exactly nothing compared to the real situation where the universe is many billions of years old and you actually did bake the cake: You can enjoy the cake in both situations, if others taste the cake they might make you a compliment, etc.
So the question is irrelevant.
Of the four questions quoted above, I would say it's the first question that is the most interesting, because some animals and toddlers apparently *don't* know that things still exist despite lack of direct sensory input. It seems like this kind of knowledge requires a tiny bit more experience and intelligence, so it's interesting from a learning and development-of-the-brain perspective.
(There is also the aspect that obviously you don't actually know with mathematical certainty that the thing still exists, but that aspect leads down to pointlessness, because you essentially never know anything at all with mathematical certainty except for mathematics itself.)