We might all be watching shadows and calling them the whole of reality

Plato imagined prisoners chained in a cave since birth, facing a wall, seeing only shadows cast by objects behind them. To the prisoners, the shadows are reality itself. One escapes, sees the true world outside, and returns to tell the others — who don't believe him. It's a 2,400-year-old warning about mistaking your limited view for the whole picture.

— Plato, The Republic, Book VII — c. 375 BC — public domain
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