“It wasn't money or love that I was looking for. I had a heightened sense of awareness, was set in my ways, impractical and a visionary to boot. My mind was strong like a trap and I didn't need any guarantee of validity.”

Letter to Thomas Poole (16 October 1797).
Letters
Context: From my early reading of Faery Tales, & Genii &c &c — my mind had been habituated to the Vast — & I never regarded my senses in any way as the criteria of my belief. I regulated all my creeds by my conceptions not by my sight — even at that age. Should children be permitted to read Romances, & Relations of Giants & Magicians, & Genii? — I know all that has been said against it; but I have formed my faith in the affirmative. — I know no other way of giving the mind a love of "the Great," & "the Whole." — Those who have been led by the same truths step by step thro' the constant testimony of their senses, seem to me to want a sense which I possess — They contemplate nothing but parts — and are parts are necessarily little — and the Universe to them is but a mass of little things. It is true, the mind may become credulous and prone to superstition by the former method; — but are not the experimentalists credulous even to madness in believing any absurdity, rather than believe the grandest truths, if they have not the testimony of their own senses in their favor? I have known some who have been rationally educated, as it is styled. They were marked by a microscopic acuteness; but when they looked at great things, all became a blank, and they saw nothing, and denied that any thing could be seen, and uniformly put the negative of a power for the possession of a power, and called the want of imagination judgment, and the never being moved to rapture philosophy.

Variant: I needed to hear the world but didn't want the world to know I was listening.
Source: The Impossible Knife of Memory

Source: Flipped

New York Times (July 2, 2004)

Foreword
LSD : My Problem Child (1980)
Context: In studying the literature connected with my work, I became aware of the great universal significance of visionary experience. It plays a dominant role, not only in mysticism and the history of religion, but also in the creative process in art, literature, and science. More recent investigations have shown that many persons also have visionary experiences in daily life, though most of us fail to recognize their meaning and value. Mystical experiences, like those that marked my childhood, are apparently far from rare.

As quoted in Willem De Kooning, 1904-1997: Content as a Glimpse by Barbara Hess, 2004.
1990's & from posthumous publications