  We put forth the idea that Hamilton's equations coincide with deterministic
and reversible evolution. We explore the idea from five different perspectives
(mathematics, measurements, thermodynamics, information theory and state
mapping) and we show how they in the end coincide. We concentrate on a single
degree of freedom at first, then generalize. We also discuss possible
philosophical reasons why the laws of physics can only describe such processes,
even if others must exist.
