The Psychology of Salesmanship

"[...]manner, etc., to do with salesmanship? Just this much, that all these things are based on the same fundamental principles as is salesmanship, and that these fundamental principles are those of psychology. All that has been said refers to psychology—all is the effect of psychology pure and simple. All depends upon the mental attitude, the suggestions offered, the mental states induced, the motive to the will—all these outward things are merely the effects of inner[...]".