The historian Thomas Carlyle considered Muhammad one of the world's greatest heroes, yet even he called the Koran "as toilsome reading as I ever undertook; a wearisome, confused jumble."
Povjesničar Thomas Carlyle je smatrao Muhameda jednim od najvećih svjetskih heroja, no i on je nazvao Kuran, "Zamornije štivo koje sam ikada uzeo, dosadna, zbunjujuća hrpa".