We say justly that the weak person is flat, for, like all flat substances, he does not stand in the direction of his strength, that is, on his edge, but affords a convenient surface to put upon. He slides all the way through life.... But the brave man is a perfect sphere, which cannot fall on its flat side and is equally strong every way.
Henry David Thoreau, Odell Shepard (1961). “The Heart of Thoreau's Journals”, p.8, Courier Corporation