“Guys are great before you know who they are,' said Lucy. 'They're great when you're still with who they might be.”

Source: Git-R-Done (book), p. 5

Revenge for Honour, Act V, scene ii; reported in Bartlett's Familiar Quotations, 10th ed. (1919).
Disputed

Source: John Lennon: In His Own Words

The Pride is Back

Joan Rivers Comedy Central Roast (2009)

Source: Fred Willard Quotes - Fred Willard on Comedy, Celebrity ... at esquire.com, Dec. 20, 2010.

Source: City of Ashes

Source: Dandelion Wine (1957), p. 142
Context: “I don’t know,” he admitted.
“Well.” She started pouring tea. “To start things off, what do you think of the world?”
“I don’t know anything.”
“The beginning of wisdom, as they say. When you’re seventeen you know everything. When you’re twenty-seven if you still know everything you’re still seventeen.”
“You seem to have learned quite a lot over the years.”
“It is the privilege of old people to seem to know everything. But it’s an act and a mask, like every other act and mask. Between ourselves, we old ones wink at each other and smile, saying, How do you like my mask, my act, my certainty? Isn’t life a play? Don’t I play it well?”
They both laughed quietly.

Fiction, The Call of Cthulhu (1926)
Context: They worshipped, so they said, the Great Old Ones who lived ages before there were any men, and who came to the young world out of the sky. Those Old Ones were gone now, inside the earth and under the sea; but their dead bodies had told their secrets in dreams to the first men, who formed a cult which had never died. This was that cult, and the prisoners said it had always existed and always would exist, hidden in distant wastes and dark places all over the world until the time when the great priest Cthulhu, from his dark house in the mighty city of R'lyeh under the waters, should rise and bring the earth again beneath his sway. Some day he would call, when the stars were ready, and the secret cult would always be waiting to liberate him.