  Higher-form symmetries are associated with transformations that only act on
extended objects, not on point particles. Typically, higher-form symmetries
live alongside ordinary, point-particle (0-form), symmetries and they can be
jointly described in terms of a direct product symmetry group. However, when
the actions of 0-form and higher-form symmetries become entangled, a more
general mathematical structure is required, related to higher categorical
groups. Systems with continuous higher-group symmetry were previously
constructed in a top-down manner, descending from quantum field theories with a
specific mixed 't Hooft anomaly. I show that higher-group symmetry also
naturally emerges from a bottom-up, low-energy perspective, when the physical
system at hand contains at least two different given, spontaneously broken
symmetries. This leads generically to a hierarchy of emergent higher-form
symmetries, corresponding to the Grassmann algebra of topological currents of
the theory, with an underlying higher-group structure. Examples of physical
systems featuring such higher-group symmetry include superfluid mixtures and
variants of axion electrodynamics.
