The best authorities on salesmanship and advertising now recognize this fact and emphasize it in their writings. George French, in his "_Art and Science of Advertising_" says regarding psychology in advertising: "So we can dismiss the weird word, and simply acknowledge that we can sell things to a man more readily if we know the man. We can't personally know every man to whom we wish to sell goods. We must therefore consider if there are not certain ways of thinking and of acting which are common to all men, or to a large proportion of men. If we can discover the laws governing the action of men's minds we will know how to appeal to those men. We know how to appeal to Smith, because we know Smith. We know what will please Brown, because we know Brown. We know how to get our way with Jones, because we know Jones. What the advertiser must know is how to get at Smith, Brown, and Jones without knowing any of them. While every man has his personal peculiarities, and while every mind has its peculiar method of dealing with the facts of life, every man and every mind is controlled, in a large sense and to a great extent, by predilections and mind-workings which were established before he lived, and are operated in a manner separate from his personality. Our minds are more automatic, more mechanical, than we are willing to admit. That which we loosely call mind is largely the automatic expression of tendencies controlled by physical conditions wholly apart from conscious intellectual or moral motives or qualities. What those physical conditions are, and how the knowledge of what they are may be utilized by advertisers, forms the body of that new knowledge some like to call psychology, so far as it concerns advertising." Mr. French has well expressed the idea of the important part played in business by psychology. What he says is, of course, as applicable to personal salesmanship as to salesmanship through advertisements--the same principles are present and operative in both cases. In order to bring to the mind of the reader the full idea of the operation of psychological principles in the sale of goods, we shall mention a few particular instances in which these principles have played a part. Each reader will be able to recollect many similar instances, once his attention is called to the matter.