“The utopian element in politics lies in the ability to disentangle the image of possible human association from forms of life that make people's material and moral ability depend on their acceptance of predetermined hierarchical and communal divisions. The struggle of this visionary politics is to deny the identification of society with a limited repertory of social forms. Such a repertory imprisons all experiments in practical collaboration, in self-expression and reconciliation, within a determinate scheme of ranks and divisions, of authoritative ideals, and of accepted contexts for the realization of these ideals.”

"Where in the World Are We?" (2006)

Source: Plasticity Into Power: Comparative-Historical Studies on the Institutional Conditions of Economic and Military Success (1987), p. 160

The Great Illusion (1910)
Context: The fight for ideals can no longer take the form of fight between nations, because the lines of division on moral questions are within the nations themselves and intersect the political frontiers. There is no modern State which is completely Catholic or Protestant, or liberal or autocratic, or aristocratic or democratic, or socialist or individualist; the moral and spiritual struggles of the modern world go on between citizens of the same State in unconscious intellectual cooperation with corresponding groups in other states, not between the public powers of rival States.

Source: False Necessityː Anti-Necessitarian Social Theory in the Service of Radical Democracy (1987), p. 467

Source: Law in Modern Societyː Toward a Criticism of Social Theory (1976), p. 260

[O] : Introduction, 0.8
Semiotics and the Philosophy of Language (1984)
Context: Certainly, the categories posited by a general semiotics can prove their power insofar as they provide a satisfactory working hypothesis to specific semiotics. However, they can also allow one to look at the whole of human activity from a coherent point of view. To see human beings as signifying animals — even outside the practice of verbal language — and to see that their ability to produce and to interpret signs, as well as their ability to draw inferences, is rooted in the same cognitive structures, represent a way to give form to our experience. There are obviously other philosophical approaches, but I think that this one deserves some effort.

Human Nature and Social Theory (1969)
Context: What about the utopian thinkers of all ages, from the Prophets who had a vision of eternal peace, on through the Utopians of the Renaissance, etc.? Were they just dreamers? Or were they so deeply aware of new possibilities, of the changeability of social conditions, that they could visualize an entirely new form of social existence even though these new forms, as such, were not even potentially given in their own society? It is true that Marx wrote a great deal against utopian socialism, and so the term has a bad odor for many Marxists. But he is polemical against certain socialist schools which were, indeed, inferior to his system because of their lack of realism. In fact, I would say the less realistic basis for a vision of the uncrippled man and of a free society there is, the more is Utopia the only legitimate form of expressing hope. But they are not trans-historical as, for instance, is the Christian idea of the Last Judgment, etc. They are historical, but the product of rational imagination, rooted in an experience of what man is capable of and in a clear insight into the transitory character of previous and existing society.

As quoted in Wisdom for the Soul: Five Millennia of Prescriptions for Spiritual Healing (2006) by Larry Chang, p. 43

The Tragic Sense of Life (1913), VII : Love, Suffering, Pity