“The dreamers are the saviors of the world. As the visible world is sustained by the invisible, so men, through all their trials and sins and sordid vocations, are nourished by the beautiful visions of their solitary dreamers.”

Source: The Critic as Artist

Beautiful Dreamer, Firth, Pond & Co. (1862).

Theatrum Chemicum Volume 1 Spec. phil.

Children of the Albatross (1947)
Context: In the world of the dreamer there was solitude: all the exaltations and joys came in the moment of preparation for living. They took place in solitude. But with action came anxiety, and the sense of insuperable effort made to match the dream, and with it came weariness, discouragement, and the flight into solitude again. And then in solitude, in the opium den of remembrance, the possibility of pleasure again.

"The Dreamer"
Beasts and Super-Beasts (1914)

Source: Personal Success

Preface.
A History of Science Vol.1 Ancient Science Through the Golden Age of Greece (1952)
Context: Some men are abstract-minded, and they naturally think first of unity and God, of wholeness, of infinity and other such concepts, while the minds of other men are concrete and they cogitate about health and disease, profit and loss. They invent gadgets and remedies; they are less interested in knowing anything than in applying whatever knowledge... to practical problems... The first are called dreamers; the second kind are recognized as practical and useful. History has often proved the shortsightedness of the practical men and vindicated the "lazy" dreamers; it has also proved that the dreamers are often mistaken.