William Walker Atkinson 
Psychology of Salesmanship 

The man in business has heard much of late regarding psychology in business affairs, and has read something on the subject. He understands that psychology plays a most important part in business, and that it is worth his while to acquaint himself with its fundamental principles. In fact, if he has thought sufficiently on the subject, he will have seen that the entire process of selling goods, personally, or by means of advertising or display, is essentially a mental process depending upon the state of mind induced in the purchaser, and that these states of mind are induced solely by reason of certain established principles of psychology. Whether the salesman, or advertiser, realizes this or not, he is employing psychological principles in attracting the attention, arousing the interest, creating the desire, and moving the will of the purchaser of his goods. This book shows you how to maximize your sales through the use of modern techniques of psychology.