“Had in him those brave translunary things
That the first poets had.”

As quoted in The Reader's Digest, Vol. 128 (1986), p. 137; later in Quotable Quotes (1997) by Editors of Reader's Digest

Odes, Book iv, Ode 9, reported in William Warburton, The Works of Alexander Pope, Esq (1751) p. 31.

After defeating Sonny Liston for the first time (25 February 1964) as quoted in Sound and Fury : Two Powerful Lives, One Fateful Friendship (2007) by Dave Kindred, p. 58
Variant transcription: I'm the greatest thing that ever lived. I'm so great I don't have a mark on my face. I shook up the world.
As quoted in "When Clay shook up the world" (24 February 2004) http://news.bbc.co.uk/sport1/hi/boxing/3516241.stm
Context: I knew I had him in the first round. Almighty God was with me. I want everyone to bear witness, I am the greatest! I'm the greatest thing that ever lived. I don't have a mark on my face, and I upset Sonny Liston, and I just turned twenty-two years old. I must be the greatest. I showed the world. I talk to God everyday. I know the real God. I shook up the world, I'm the king of the world. You must listen to me. I am the greatest! I can't be beat!

Source: Alexander the Great, 1973, p.71

his testament for posterity. Ooof!
Ch 23
A Canticle for Leibowitz (1959), Fiat Lux

The Inferno (1917), Ch. XIV
Context: I thought of all those wise men, poets, artists before me who had suffered, wept, and smiled on the road to truth. I thought of the Latin poet who wished to reassure and console men by showing them truth as unveiled as a statue. A fragment of his prelude came to my mind, learned long ago, then dismissed and lost like almost everything that I had taken the pains to learn up till then. He said he kept watch in the serene nights to find the words, the poem in which to convey to men the ideas that would deliver them. For two thousand years men have always had to be reassured and consoled. For two thousand years I have had to be delivered. Nothing has changed the surface of things. The teachings of Christ have not changed the surface of things, and would not even if men had not ruined His teachings so that they can no longer follow them honestly. Will the great poet come who shall settle the boundaries of belief and render it eternal, the poet who will be, not a fool, not an ignorant orator, but a wise man, the great inexorable poet? I do not know, although the lofty words of the man who died in the boarding-house have given me a vague hope of his coming and the right to adore him already.

Letter to James Laughlin (14 January 1944), published in The Selected Letters of William Carlos Williams (1957) edited by John C. Thirlwall, p. 219
General sources

Source: I Am Legend (1954), Ch. 16
Context: All these years, he thought, dreaming about a companion. Now I meet one and the first thing I do is distrust her, treat her crudely and impatiently.
And yet there was really nothing else he could do. He had accepted too long the proposition that he was the only normal person left. It didn’t matter that she looked normal. He’d seen too many of them lying in their coma that looked as healthy as she. They weren’t, though, and he knew it. The simple fact that she had been walking in the sunlight wasn’t enough to tip the scales on the side of trusting acceptance. He had doubted too long. His concept of the society had become ironbound. It was almost impossible for him to believe that there were others like him. And, after the first shock had diminished, all the dogma of his long years alone had asserted itself.

As quoted in "Saroyan's Literary Quarantine" http://www.cilicia.com/armo22_william_saroyan_2.html by Peter H. King, in The Los Angeles Times (26 March 1997).