The Quran 22:46 (Surah al-Haj)

“It is not the eyes that are blind, but the hearts.”

Complete Verse (Translated by Yusuf Ali):

“Do they not travel through the land, so that their hearts (and minds) may thus learn wisdom and their ears may thus learn to hear? Truly it is not their eyes that are blind, but their hearts which are in their bosoms.”