  We present ongoing investigations of a four-dimensional lattice field theory
with four massless reduced staggered fermions coupled through an
SU(4)-invariant four-fermion interaction. As in previous studies of
four-fermion and Higgs--Yukawa models with different lattice fermion
discretizations, we observe a strong-coupling phase in which the system
develops a mass gap without breaking any lattice symmetry. This symmetric
strong-coupling phase is separated from the symmetric weak-coupling phase by a
narrow region of four-fermi coupling in which the system exhibits long-range
correlations.
