Now is there any person living of that industrious, pliant, and universal humor, who can take the pains exactly to imitate all shapes, and will not rather deride the advice of Theognis as absurd and impossible, namely, to learn the craft of the polypus, which puts on the hue of every stone it sticks to? However, the changes of this fish are only superficial, and the colors are produced in the skin, which by its closeness or its laxity receives various impressions from neighboring objects; whereas the resemblance betwixt friends must be far more than skin-deep, must be substantial, such as may be traced in every action of their lives, in all their affections, dispositions, words and purposes, even to their most retired thoughts. To follow the advice of Theognis would be a task worthy of a Proteus, who was neither very fortunate nor very honest, but could by enchantment transform himself in an instant from one shape to another. Even so, he that entertains many friends must be learned and bookish among the learned, go into the arena with wrestlers, drudge cheerfully after a pack of hounds with gentlemen that love hunting, drink with debauchees, and sue for office with politicians; in fine, he must have no proper principles of actions and tumors of his own, but those of the present company he converses with. Thus, as the first matter of the philosophers is originally without shape or color, yet being the subject of all natural changes takes by its own inherent forces the forms of fire, water, air, and solid earth; so a person that affects a numerous friendship must possess a mind full of folds and windings, subject to many passions, inconstant as water, and easy to be transformed into an infinite variety of shapes. But real friendship requires a sedate, stable, and unalterable temper; so that it is a rare thing and next a miracle to find a constant and sure friend.