In human perception, ''//the contrast principle//'', that affects the way we see the difference between two things that are presented one after another. Simply put, if the second item is fairly different from the first, we will tend to see it as more different than it actually is. So if we lift a light object first and then lift a heavy object, we will estimate the second object to be heavier than if we had lifted it without first trying the light one. The contrast principle is well established in the Field of psychophysics and applies to allsorts of perceptions besides weight. !Examples * If we are talking to a beautiful woman at a cocktail party and are then joined by an unattractive one, the second woman will strike us as less attractive than she actually is. * Studies done on the contrast principle at Arizona State and Montana State universities suggest that we may be less satisfied with the physical attractiveness of our own lovers because of the way the popular media bombard us with of unrealistically attractive models. * The same principle applies to a man who wishes to buy the accessories (shirt, shoes, belt) to go along with his new suit. Contrary to the commonsense view, the evidence supports the contrast-principle prediction. * The interesting thing is that even when a man enters a clothing store with the express purpose of purchasing a suit, he will almost always pay more for whatever accessories he boys ifhe boys them ujqer the suit purchase than before.” * It is much more profitable for salespeople to present the expensive item first, not only because to fail to do so will lose the influence of the contrast principle; to fail to do so will also cause the principle to work actively against them. * Presenting an inexpensive product first and following it with an expensive one will cause the expensive item to seem even more costly as a result-hardly a desirable consequence for most sales organizations.