that man’s supremacy is not primarily due to his brain, as most of the books would have one think. It is due to the brain’s capacity to make use of the information conveyed to it by a narrow band of visible light rays. His civilization, all that he had achieved or might achieve, hung upon his ability to perceive that range of vibrations from red to violet. Without that, he was lost. I saw for a moment the true tenuousness of his hold on his power, the miracles that he had wrought with such a fragile instrument….
