Now, as I have pointed out, the most plastic ma terial, which most easily and most nearly approximates a physical manifestation of this spirit, is undoubtedly the wilderness. There each of its aspects or attributes finds satisfaction in the most direct terms. There a man can find room, physical room, in wide spaces under distant stars, to reach outward in the utmost expansion of which he is capable. He meets the conditions of life face to face and personally. The lowest terms of bare existence he must accomplish before he can proceed on his quest — or even survive. Warmth, food, and shelter — the three essentials — are to be had only by the exercise of his wits and hands. And the strong stark primitive forces of nature are always ready with their tests of his physical and moral strength. Man matches himself against the world-wide never-changing forces of the Wilderness, and through them gains a measure of himself.