But of all attachments to an individual, that which is founded altogether upon esteem and approbation of his good conduct and behaviour, confirmed by much experience and long acquaintance, is, by far, the most respectable. Such friendships, arising not from a constrained sympathy, not from a sympathy which has been assumed and rendered habitual for the sake of convenience and accommodation; but from a natural sympathy, from an involuntary feeling that the persons to whom we attach ourselves are the natural and proper objects of esteem and approbation; can exist only among men of virtue. Men of virtue only can feel that entire confidence in the conduct and behaviour of one another, which can, at all times, assure them that they can never either offend or be offended by one another. Vice is always capricious: virtue only is regular and orderly. The attachment which is founded upon the love of virtue, as it is certainly, of all attachments, the most virtuous; so it is likewise the happiest, as well as the most permanent and secure. Such friendships need not be confined to a single person, but may safely embrace all the wise and virtuous, with whom we have been long and intimately acquainted, and upon whose wisdom and virtue we can, upon that account, entirely depend. They who would confine friendship to two persons, seem to confound the wise security of friendship with the jealousy and folly of love. The hasty, fond, and foolish intimacies of young people, founded, commonly, upon some slight similarity of character, altogether unconnected with good conduct, upon a taste, perhaps, for the same studies, the same amusements, the same diversions, or upon their agreement in some singular principle or opinion, not commonly adopted; those intimacies which a freak begins, and which a freak puts an end to, how agreeable soever they may appear while they last, can by no means deserve the sacred and the venerable name of friendship.