  Two dimensional toy models display, in a gentler setting, manysalient aspects
of Quantum Field Theory. Here I discuss a concrete two dimensional case, the
Thirring model, which illustrates several important concepts of this theory:
the anomalous dimension of the fields; the exact solvability; the anomalies of
the Ward-Takahashi identities. Besides, I give a glimpse of the decisive role
that this model plays in the study of an apparently unrelated topic:
correlation critical exponents of two dimensional lattice systems of
Statistical Mechanics.
