comes from the musical play "Man of La Mancha" which is based on Don Quixote and comes after a dialogue between Don Quixote and Aldonza as they discuss Don Quixote's "Quest":DON QUIXOTEIt is the mission of each true knight...His duty... nay, his privilege!To dream the impossible dream,To fight the unbeatable foe,To bear with unbearable sorrowTo run where the brave dare not go;To right the unrightable wrong.To love, pure and chaste, from afar,To try, when your arms are too weary,To reach the unreachable star!This is my Quest to follow that star,No matter how hopeless, no matter how far,To fight for the rightWithout question or pause,To be willing to march into hellFor a heavenly cause!And I know, if I'll only be trueTo this glorious Quest,That my heart will lie peaceful and calmWhen I'm laid to my rest.And the world will be better for this,That one man, scorned and covered with scars,Still strove, with his last ounce of courage,To reach the unreachable stars! 

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