  Conservation laws are the pillars of physics. It's what we held on to when
our imagination was challenged during the days of relativity or quantum
mechanics. Their violation leads to the most absurd models, so excellently
exercised in the history of the perpetuum mobile. Importantly, it is not at all
sufficient to merely accept the existence of conservation laws. Intention to
obey them is required when models are developed, as conservation laws are not
obeyed simply by accident. However evident this demand may appear, its
application turns out to be quite delicate and the scientific debate of
Maxwell's Demon is a beautiful demonstration of this delicateness. Here I
comment on the general violation of conservation laws in most common textbook
models of biological communication and outline a different route forward using
the example of nerve pulse propagation.
