"A man," says Emerson, "is like a bit of Labrador spar, which has no lustre as you turn it in your hand until you come to a particular angle; then it shows deep and beautiful colors." There is no adaptation or universal applicability in man; but each has his special talent; and the mastery of successful men consists in adroitly keeping themselves where and when that turn shall need oftenest to be practiced. The successful man in every calling, whether literary, scientific or business, is he who is _totus in illo_--who can say with Paul, this one thing I do! With the exception of a few great creative minds, the men whose names are historic are identified with some one achievement, upon which all their life force is spent. "Whatever I have tried to do in my life," says Dickens, "I have tried with all my heart to do well. What I have devoted myself to, I have devoted myself to completely. Never to put one hand to a thing on which I would not throw my whole self, and never to affect depreciation of my work, whatever it was, I find now to have been golden rules." The fact is, the range of human knowledge has become so extensive that the man who would know some things well must have the courage to be ignorant of many others. There are many things for which one is wholly incapacitated; for which he has no talent, and, as a rule, time spent in this direction is time lost. Goethe justly says: "We should guard against a talent which we can not hope to practice in perfection. Improve it as we may, we shall always, in the end, when the merit of the master has become apparent to us, painfully lament the loss of time and strength devoted to such botching." Sidney Smith condemns what he calls the "foppery of _universality_--of knowing all sciences and excelling in all arts." "Now _my_ advice," he says, "on the contrary, is to have the courage to be ignorant of a great number of things, in order to avoid the calamity of being ignorant of everything."