is worse than shallow to generalize at all about comparative behavior until there is a measurable similarity between the environments to which behavior is a response.
The pragmatic value of this idea is that it introduces a much needed refinement into the ancient controversy about nature and nurture, innate quality and environment. For the pseudo-environment is a hybrid compounded of "human nature" and "conditions." To my mind it shows the uselessness of pontificating about what man is and always will be from what we observe man to be doing, or about what are the necessary conditions of society. For we do not know how men would behave in response to the facts of the Great Society. All that we really know is how they behave in response to what can fairly be called a most inadequate picture of the Great Society. No conclusion about man or the Great Society can honestly be made on evidence like that.
This, then, will be the clue to our inquiry. We shall assume that what each man does is based not on direct and certain knowledge, but on pictures made by himself or given to him. If his atlas tells him that the world is flat he will not sail near what he believes to be the edge of our planet for fear of falling off. If his maps include a fountain of eternal youth, a Ponce de Leon will go in quest of it. If someone digs up yellow dirt that looks like gold, he will for a time act exactly as if he had found gold. The way in which the world is imagined determines at any particular moment what men will do. It does not
