Utopianism is a persistent tradition of thought about the perfect society, in which perfection is defined as harmony.
Utopia is the ideology of revolt, of religious and political aspiration, of apocalyptic and messianic dreams, of the future.
No society fully understands itself and its potential. Therefore what appears over-utopian may be realizable, whereas what appears realistic may be impossible to achieve. Utopian visions, even when not realizable, may therefore bring about meaningful changes. Indeed, whether adopted by political movements or not, they may constitute a main mode of human evolution which should not be constrained by feasibility assessments.