  Here we point out that the four-nucleon terms incorporate into lowest order
non-linear chiral effective Lagrangians the same description of bulk nuclear
matter contained in the Walecka model, that is generally considered
satisfactory. We find this point worth noticing because, while the Walecka
model is an entirely phenomenological renormalizable model, non-linear chiral
Lagrangians have a deep basis in elementary particle physics, and, in this
sense, are more fundamental.
