No wealth can buy the requisite leisure, freedom, and independence which are the capital in this profession. It comes only by the grace of God. It requires a direct dispensation from Heaven to become a walker. You must be born into the family of the Walkers. Ambulator nascitur, non fit.
Henry David Thoreau (1817–1862), U.S. philosopher, author, naturalist. "Walking" (1862), in The Writings of Henry David Thoreau, vol. 5, p. 207, Houghton Mifflin (1906).
Thoreau's Latin ("The walker is born, not made") is a play off of famous tags from Horace and Sir Philip Sidney on the subject of literary inspiration and education: Orator (or alternatively poeta) nascitur, non fit ("the orator" or "the poet is born, not made").