  We present a clear and mathematically simple procedure explaining spontaneous
symmetry breaking in quantum mechanical systems. The procedure is applicable to
a wide range of models and can be easily used to explain the existence of a
symmetry broken state in crystals, antiferromagnets and even superconductors.
It has the advantage that it automatically brings to the fore the main players
in spontaneous symmetry breaking: the symmetry breaking field, the
thermodynamic limit, and the global excitations of the thin spectrum.
