“Bert is super kind, a super sweetheart, but he's pretty crazy at the same time. He's a little manic, but he definitely has a great heart and a great soul. He's just a little bit hard to hold down. Which is good. It's a great quality for a frontman.”

Source: The Autobiography of Alice B. Toklas

Listen, Little Man! (1948)
Context: The Little Man does not know that he is little, and he is afraid of knowing it. He covers up his smallness and narrowness with illusions of strength and greatness, of others' strength and greatness. He is proud of his great generals but not proud of himself. He admires thought which he did not have and not the thought he did have. He believes in things all the more thoroughly the less he comprehends them, and does not believe in the correctness of those ideas which he comprehends most easily.

Attributed to Carlyle in Dale Carnegie's How to Win Friends And Influence People (1936), but this quotation is not found in Carlyle's known works. The first mention found in Google Books dates from 1908, where the Rev. John Timothy Stone https://en.wikipedia.org/wiki/John_Timothy_Stone is quoted as claiming: 'The greatest critics of this world have been appreciators. Carlyle said, "You can discover a great man, or see a great man, by the way he treats little men.'
The quotation is subsequently found in slightly different forms, mostly in religious publications: "A great man shows his greatness by manner in which he treats little men" (1913, unattributed); The exact wording of Carnegie's quote suggests that it was taken from Stone's 1930 publication.
Disputed

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 293.

" Frances Bean Cobain on Life After Kurt's Death: An Exclusive Q&A http://www.rollingstone.com/music/features/frances-bean-life-after-kurt-cobain-death-exclusive-interview-20150408" (2015)

Listen, Little Man! (1948)
Context: My intellect tells me: "Tell the truth at any cost." The Little Man in me says: "It is stupid to expose oneself to the little man, to put oneself at his mercy. The Little Man does not want to hear the truth about himself. He does not want the great responsibility which is his. He wants to remain a Little Man. He wants to remain a Little Man, or wants to become a little great man. He wants to become rich, or a party leader, or commander of a legion, or secretary of the society for the abolition of vice. But he does not want to assume responsibility for his work..."

Of the True Greatness of Kingdoms and Estates
Essays (1625)

Listen, Little Man! (1948)
Context: You are different from the really great man in only one thing: The great man, at one time, also was a very little man, but he developed one important ability: he learned to see where he was small in his thinking, and actions. Under the pressure of some task which was dear to him he learned better and better to sense the threat that comes from his smallness and pettiness. The great man, then, knows when and in what he is a little man.

"The Big Hunger" (1952)
Context: The old man was sad as he sat on his porch. He knew so little of the Great Purpose. Why must his seed fling itself starward? He knew that it must — but he lacked a reason. His grandchildren played in the twilight, played space-games, although there was not yet a starship on the planet.