“Stand up straight”

"A man who has a bad habitual posture tells himself, or is told, to stand up straight. If he is interested and responds, he braces himself, goes through certain movements, and it is assumed that the desired result is substantially attained; and that the position is retained at least as long as the man keeps the idea or order in his mind. Consider the assumptions which are here made. It is implied that the means or effective conditions of the realization of a purpose exist independently of established habit and even that they may be set in motion in opposition to habit. It is assumed that means are there, so that the failure to stand erect is wholly a matter of failure of purpose and desire. It needs paralysis or a broken leg or some other equally gross phenomenon to make us appreciate the importance of objective conditions.

Now in fact a man who can stand properly does so, and only a man who can, does. In the former case, fiats of will are unnecessary, and in the latter useless. A man who does not stand properly forms a habit of standing improperly, a positive, forceful habit. The common implication that his mistake is merely negative, that he is simply failing to do the right thing, and that the failure can be made good by an order of will is absurd.

One might as well suppose that the man who is a slave of whiskey-drinking is merely one who fails to drink water. Conditions have been formed for producing a bad result, and the bad result will occur as long as those conditions exist. They can no more be dismissed by a direct effort of will than the conditions which create drought can be dispelled by whistling for wind. It is as reasonable to expect a fire to go out when it is ordered to stop burning as to suppose that a man can stand straight in consequence of a direct action of thought and desire. The fire can be put out only by changing objective conditions; it is the same with rectification of bad posture."

— Human Nature and Conduct An introduction to social psychology by John Dewey
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