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Is there an elegant mathematical proof to assert that we cannot see more than 3 faces of an opaque solid cube simultaneously (of course without mirrors or any optical tools such as camera, etc)?

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up vote 3 down vote accepted

There are three pairs of opposite faces. To see more than three faces, you would have to view both from one pair simultaneously.

Opposite faces of the cube are parallel. If you can see a particular face, you can't see the one opposite it, because look which side of it you're on.

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But you can see 3 faces by focusing on one corner. – kiss my armpit Mar 11 '14 at 6:29
In that situation, you're still not seeing any face and its opposite at the same time. To see more than three, you would have to see some face and its opposite face at the same time. – G Tony Jacobs Mar 11 '14 at 6:30
+1. Makes sense! – kiss my armpit Mar 11 '14 at 6:31

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