The nuclear liquid--gas phase transition is treated as the phenomenon of spontaneous symmetry breaking. A quasistationary state is formed at the end of nucleon--nucleon cascade in the residue, possessing the spherical symmetry, same as the projectile and target had in their ground states. This symmetry is broken in the course of fragment formation stage, at the end of which emerges a multi-cluster configuration. The nuclear liquid--gas phase transition is thus inscribed onto the list of critical phenomena considered by synergetics.

PACS numbers: 25.70.Pq