Plato – The Republic (Book VII):
“What we see are shadows of the real; and the truth would be literally nothing but the shadows of the images.”
The Buddha – Pheṇapiṇḍūpama Sutta (SN 22.95):
“Form is like a lump of foam, feeling like a bubble, perception like a mirage… whatever is seen, heard, sensed, or cognized… is void, hollow, and insubstantial.”