“We grow great by dreams. All big men are dreamers. They see things in the soft haze of a spring day or in the red fire of a long winter's evening. Some of us let these great dreams die, but others nourish and protect them; nurse them through bad days till they bring them to the sunshine and light which comes always to those who sincerely hope that their dreams will come true.”

"Richard Fentnor Harroby" in Ch. 1 : Pallation of the Gambit
The Cream of the Jest (1917)
Context: I also begin where he began, and follow wither the dream led him. Meanwhile, I can but entreat you to remember it is only by preserving faith in human dreams that we may, after all, perhaps some day make them come true.

Introductory Chapter. Variant: This, therefore, is a faded dream of the time when I went down into the dust and noise of the Eastern market-place, and with my brain and muscles, with sweat and constant thinking, made others see my visions coming true. Those who dream by night in the dusty recesses of their minds wake in the day to find that all was vanity; but the dreamers of the day are dangerous men, for they may act their dream with open eyes, and make it possible.
Seven Pillars of Wisdom (1922)

Love is Enough (1872), Song III: It Grew Up Without Heeding

Source: Wings of Fire, p. 161.

Source: The Cream of the Jest (1917), Ch. 40 : Which Mr. Flaherty Does Not Quite Explain

Source: How to Be Like Walt : Capturing the Magic Every Day of Your Life (2004), Ch. 3 : Imagination Unlimited, p. 63; Unsourced variant: All your dreams can come true if you have the courage to pursue them.

The Queen of Air and Darkness (1939)