Man's capacities have never been measured; nor are we to judge of what he can do by any precedent, so little has been tried.
Source: In Webster's Electronic Quotebase, ed. Keith Mohler, 1994.
-- Henry David Thoreau, (Jul 12 1817-1862), US essayist, poet, naturalist; He is best known for his description of life at Walden Pond, Walden, 1854 and his essay Civil Disobedience, 1849.