A knowledge of the disposition and character of the human mind can be acquired only by experience; a great deal will be learned, I admit, by a habit of examining what passes in our bosoms, what are our own motives of action, and of what kind of sentiments we are conscious on any occasion. We may suppose an uniformity, and conclude that the same effect will be produced by the same cause in the mind of others. This examination will contribute to suggest to us matters of inquiry; but we can never be sure that our own sentiments are true and right, till they are confirmed by more extensive observation. One man opposing another determines nothing; but a general union of minds, like a general combination of the forces of all mankind, makes a strength that is irresistible. In fact, as he who does not know himself, does not know others, so it may be said with equal truth, that he who does not know others, knows himself but very imperfectly. A man who thinks he is guarding himself against prejudices by resisting the authority of others, leaves open every avenue to singularity, vanity, self-conceit, obstinacy, and many other vices, all tending to warp the judgment, and prevent the natural operation of his faculties. This submission to others is a deference which we owe, and, indeed, are forced involuntarily to pay. In fact, we never are satisfied with our opinions, whatever we may pretend, till they are ratified and confirmed by the suffrages of the rest of mankind. We dispute and wrangle for ever; we endeavour to get men to come to us when we do not go to them. He, therefore, who is acquainted with the works which have pleased different ages and different countries, and has formed his opinion on them, has more materials, and more means of knowing what is analogous to the mind of man, than he who is conversant only with the works of his own age or country. What has pleased, and continues to please, is likely to please again: hence are derived the rules of art, and on this immovable foundation they must ever stand. This search and study of the history of the mind ought not to be confined to one art only. It is by the analogy that one art bears to another that many things are ascertained, which either were but faintly seen, or, perhaps, would not have been discovered at all, if the inventor had not received the first hints from the practices of a sister art on a similar occasion.[6] The frequent allusions which every man who treats of any art is obliged to make to others, in order to illustrate and confirm his principles, sufficiently show their near connection and inseparable relation. All arts having the same general end, which is to please; and addressing themselves to the same faculties, through the medium of the senses; it follows that their rules and principles must have as great affinity as the different materials and the different organs or vehicles by which they pass to the mind will permit them to retain.[7]