Experiments in communal living were utopian. The word "utopia" literally means "no place," and therein lies the problem. A utopia, as a result of its very nature, does not exist anywhere. Many tried to establish utopian settlements, especially in nineteenth century America, but none succeeded. One reason is that societies, especially successful ones, arise naturally and slowly develop over time. Societies evolve through the needs of individuals, initially basic needs such as food, warmth, and shelter, but societies eventually bond over more sophisticated needs such as transport, defense, and communications. This is the main thing that distinguishes a natural society from a utopian experiment—in the latter, the needs of society are imposed from above as part of a blueprint based on abstract ideas.
In order to survive, healthy societies must change and adapt. However, a utopian community is unable to do so precisely because it is based on an abstract idea, one that has no practical application to the real world. Such communities are founded on an ideal, and ideals of this nature cannot be changed. Living up to an ideal, however noble, puts an enormous strain on people. Most of us live our lives according to certain moral values, but if we fail to live up to the standards we set for ourselves, we can always try to do better next time. Mature societies can tolerate a fair amount of backsliding among its members. The same cannot be said of utopian communities. If their members cannot maintain an often impossible degree of fidelity to the ideals on which such communities are based, then the whole experiment will begin to unravel, and, eventually, it will collapse. That is precisely what happened in nineteenth-century America and elsewhere.