Philosophers have always tried to find out what's real and true by discovering and stripping away what's mistaken and apparent. They've asked fundamental questions about reality, and have uncovered ambiguities and contradictions which have given rise to long-standing disagreements. Different philosophers have had different worries about reality. This essay is about what's puzzled me personally, and how I've organised my ideas about it so far.
Our knowledge of the physical world outside our minds ["objective reality"] can only come to us via our own perceptions of it. Those pictures in our minds are clearly a different thing from the world itself. We assume that the two are very intimately related. Indeed, we assume that the world is exactly represented by our perceptions. But this isn't necessarily true. In fact, thought and experiment show that it's far from true. So what is the nature of the real world, and what is the relationship between that world and our perceptions of it?
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