No sadder proof can be given by a man of his own littleness than disbelief in great men.

Thomas Carlyle
Thomas Carlyle (1795–1881) Scottish essayist and historian
Lecture (1840-05-05), “The Hero as Divinity,” Home House, Portman Square, London
    (Source)

The lecture notes were collected by Carlyle into On Heroes, Hero-Worship, & the Heroic in History, Lecture 1, (1841).