  This paper proves that protomechanics, previously introduced in
quant-ph/9909025, deduces both quantum mechanics and classical mechanics. It
does not only solve the problem of the arbitrariness on the operator ordering
for the quantization procedure, but also that of the analyticity at the exact
classical-limit of $\hbar =0 $. In addition, proto-mechanics proves valid also
for the description of a half-spin.
