But if the physical environment is the earth, the world of ideas corresponds to the heavens. We sleep under the light of stars that have long since ceased to exist, and we pattern our behavior by ideas which have no reality as soon as we cease to credit them. Whilst it holds together this world of ideas--this idolum--is almost as sound, almost as real, almost as inescapable as the bricks of our houses or the asphalt beneath our feet. The “belief” that the world was flat was once upon a time more important than the “fact” that it was round; and that belief kept the sailors of the medieval world from wandering out of sight of land as effectively as would a string of gun-boats or floating mines. An idea is a solid fact, a theory is a solid fact, a superstition is a solid fact as long as people continue to regulate their actions in terms of the idea, theory, or superstition; and it is none the less solid because it is conveyed as an image or a breath of sound. 3 This world of ideas serves many purposes. Two of them bear heavily upon our investigation of utopia. On one hand the pseudo-environment or idolum is a substitute for the external world; it is a sort of house of refuge to which we flee when our contacts with “hard facts” become too complicated to carry through or too rough to face. On the other hand, it is by means of the idolum that the facts of the everyday world are brought together and assorted and sifted, and a new sort of reality is projected back again upon the external world. One of these functions is escape or compensation; it seeks an immediate release from the difficulties or frustrations of our lot. The other attempts to provide a condition for our release in the future. The utopias that correspond to these two functions I shall call the utopias of escape and the utopias of reconstruction. The first leaves the external world the way it is; the second seeks to change it so that one may have intercourse with it on one’s own terms. In one we build impossible castles in the air; in the other we consult a surveyor and an architect and a mason and proceed to build a house which meets our essential needs; as well as houses made of stone and mortar are capable of meeting them. 4