-blind cannot be severed from the life of the seeing, hearing
race.

The deaf-blind person may be plunged and replunged like Schiller's
diver into seas of the unknown. But, unlike the doomed hero, he returns
triumphant, grasping the priceless truth that his mind is not crippled,
not limited to the infirmity of his senses. The world of the eye and the
ear becomes to him a subject of fateful interest. He seizes every word
of sight and hearing because his sensations compel it. Light and colour,
of which he has no tactual evidence, he studies fearlessly, believing
that all humanly knowable truth is open to him. He is in a position
similar to that of the astronomer who, firm, patient, watches a star
night after night for many years and feels rewarded if he discovers a
single fact about it. The man deaf-blind to ordinary outward things, and
the man deaf-blind to the immeasurable universe, are both limited by
time and space; but they have made a compact to wring service from their
limitations.

The bulk of the world's knowledge is an imaginary construction. History
is but a mode of imagining, of making us see civilizations that no
longer appear upon the earth. Some of the most significant discoveries
in modern science owe their origin to the imagination of men who had
neither accurate knowledge nor exact instruments to demonstrate their
beliefs. If astronomy had not kept always in advance of the telescope,
no one would ever have thought a telescope worth making. What great
invention has not existed in the inventor's mind long before he gave it
tangible shape?

A more splendid example of imaginative knowledge is the unity with which
philosophers start their study of the world. They can never perceive the
world in its entire reality. Yet their imagination, with its magnificent
allowance for error, its power of treating uncertainty as negligible,
has pointed the way for empirical knowledge.

In their highest creative moments the great poet, the great musician
cease to use the crude instruments of sight and hearing. They break away
from their sense-moorings, rise on strong, compelling wings of spirit
far above our misty hills and darkened valleys into the region of light,
music, intellect.

What eye hath seen the glories of the New Jerusalem? What ear hath heard
the music of the spheres, the steps of time, the strokes of chance, the
blows of death? Men have not heard with their physical sense the tumult
of sweet voices above