Abstract. Phase transitions, equilibrium and nonequilibriurn, are hallmarked by symmetry changes. The latter are phenomenologically expressed by the introduction of order parameters. The external influences, however, which are represented, generally have different symmetry. The relationship between the symmetry of external influences and the symmetry of emerging phases is considered on the basis of Curie's principle connecting dissymmetries of causes to those of consequences. The difference is expounded between forced (organized) and spontaneous (self-organized) ordering in various condensed-matter systems.

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