In The Malloreon, the last book I think, the Voice that speaks in Garion's head explains the speed of sound to him, using the memory of seeing someone cutting wood a long way away and hearing the sound of the axe hitting well after seeing it hit. Once he's grasped and accepted that, the Voice then goes on to explain that light has a speed, too.
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Big Brother is watching you. And damn, you are so bloody BORING.
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Big Brother is watching you. And damn, you are so bloody BORING.