Books delight us, when prosperity smiles upon us; they comfort us inseparably when stormy fortune frowns on us. They lend validity to human compacts, and no serious judgments are propounded without their help. Arts and sciences, all the advantages of which no mind can enumerate, consist in books. How highly must we estimate the wondrous power of books, since through them we survey the utmost bounds of the world and time, and contemplate the things that are as well as those that are not, as it were in the mirror of eternity. In books we climb mountains and scan the deepest gulfs of the abyss; in books we behold the finny tribes that may not exist outside their native waters, distinguish the properties of streams and springs and of various lands; from books we dig out gems and metals and the materials of every kind of mineral, and learn the virtues of herbs and trees and plants, and survey at will the whole progeny of Neptune, Ceres, and Pluto. But if we please to visit the heavenly inhabitants, Taurus, Caucasus, and Olympus are at hand, from which we pass beyond the realms of Juno and mark out the territories of the seven planets by lines and circles. And finally we traverse the loftiest firmament of all, adorned with signs, degrees, and figures in the utmost variety. There we inspect the antarctic pole, which eye hath not seen, nor ear heard; we admire the luminous Milky Way and the Zodiac, marvellously and delightfully pictured with celestial animals. Thence by books we pass on to separate substances, that the intellect may greet kindred intelligences, and with the mind's eye may discern the First Cause of all things and the Unmoved Mover of infinite virtue, and may immerse itself in love without end. See how with the aid of books we attain the reward of our beatitude, while we are yet sojourners below. Why need we say more? Certes, just as we have learnt on the authority of Seneca, leisure without letters is death and the sepulture of the living, so contrariwise we conclude that occupation with letters or books is the life of man. Again, by means of books we communicate to friends as well as foes what we cannot safely entrust to messengers; since the book is generally allowed access to the chambers of princes, from which the voice of its author would be rigidly excluded, as Tertullian observes at the beginning of his Apologeticus. When shut up in prison and in bonds, and utterly deprived of bodily liberty, we use books as ambassadors to our friends, and entrust them with the conduct of our cause, and send them where to go ourselves would incur the penalty of death. By the aid of books we remember things that are past, and even prophesy as to the future; and things present, which shift and flow, we perpetuate by committing them to writing.