__Formalism in Mechanics__

- Formalism (e.g. [Eis, p.309, l.20]® [Eis,
p.309, l.23]) is a good predictor for the pattern of generalization, but the detailed
justification of formalism requires careful analysis [Coh, p.1389,
' c].

- Formalism provides a short cut to the heart of the matter.

A good start is half of the battle. Formalism provides a
long-tested method to solve physical problems. Quantum mechanics is centered in
a system's Hamiltonian. Kittel's approach to Fermi Gas in metals starts with the Fermi
energy [Kit, p.183], while Ashcroft's approach fails to distinguish this feature
[Ashc, pp.32-36]. Therefore, Ashcroft's explanation of the Fermi energy [Ashc,
p.36, l.18] is less clear and organized than Kittel's.

- An
__unproven__ formal differentiation __neglects subtleties__ of meaning.

Example.
Compare [Coh, p.1149, (8)] with [Mer2, p.137, (8.8)].