  We present an intuitive picture of the chiral symmetry breaking in the NJL
and Thirring models. For the current current interaction model with the
massless fermion, the vacuum is realized with the chiral symmetry broken phase,
and the fermion acquires the induced mass. With this finite fermion mass, we
calculate the boson mass, and find that the boson is always massive, and there
exists no Goldstone boson in the Nambu-Jona-Lasinio (NJL) model.
