himself at the hands of Nature is better off in the open field.
Of human knowledge as a whole and in every branch of it, by far the largest part exists nowhere but on paper,—I mean, in books, that paper memory of mankind. Only a small part of it is at any given period really active in the minds of particular persons. This is due, in the main, to the brevity and uncertainty of life; but it also comes from the fact that men are lazy and bent on pleasure. Every generation attains, on its hasty passage through existence, just so much of human knowledge as it needs, and then soon disappears. Most men of learning are very superficial. Then follows a new generation, full of hope, but ignorant, and with everything to learn from the beginning. It seizes, in its turn, just so much as it can grasp or find useful on its brief journey and then too goes its way. How badly it would fare with human knowledge if it were not for the art of writing and printing! This it is that makes libraries the only sure and lasting memory of the human race, for its individual members have all of them but a very limited and imperfect one. Hence most men of learning as are loth to have their knowledge examined as merchants to lay bare their books.
Human knowledge extends on all sides farther than the eye can reach; and of that which would be generally worth knowing, no one man can possess even the thousandth part.
All branches of learning have thus been so much enlarged that he who would "do something" has to pursue no more than one subject and disregard all others.
