TD: Autogenesis is also not a Maximum Entropy Production process because it
halts dissipation before its essential self-preserving constraints are
degraded and therefore does not exhaust the gradient(s) on which its
persistence depends.
S: Abiotic dissipative structures will degrade their gradients as fast as
possible given the bearing constraints. They are unconditional maximizers.
Life that has survived has been able to apply conditions upon its entropy
production, but that does not mean that it has enacted energy conservation
or energy efficiency policies. Its mode is still maximizing, but within
limits.
GH: I think of [MEPP] as a thermodynamic version of natural selection in
which some alternative states are thermodynamically favored over others,
but this does not guarantee that dissipation will proceed to completion or
that the particular alternative that absolutely generates the most
efficient or effective dissipation will always be the manifested outcome
(if there are a number of similarly optimal paths available). Contingency
on idiosyncratic configurations within and in the neighborhood of a system
might lead the system to follow a variety of alternative paths.
S: I think that the keyword here is ‘striving’ Living things are mostly
always striving, so they reach for the maximum until it ‘hurts’.
GH: Would you argue that autogenesis is not an MEP process from this
somewhat fuzzy perspective?
TD: This offers a challenge to a theory (MEPP) that has recently been
heralded as a key to explaining life. But it does not violate the basic
logic of far-from-equilibrium thermodynamics. It is rather a further
development, that now includes a non-linear factor: dissipative processes
that collectively produce and modify their own boundary conditions. But as
with the introduction of an such nonlinearity this can produce some quite
unexpected emergent consequences. This is what makes the dynamic that we
call life so radically different in what it can do compared to non-living
dissipative dynamics.
This -snip- does suggest that we may need to modify claims that life is
"merely" an entropy maximizing process.
S: I think no one has argued that living systems are ‘merely’ entropy
production maximizers. That might be the view of the Universe, if it could
have a view. But finalities can be parsed as {entropy production {free
energy dissipation {work}}} on the template {physical process {chemical
actions {living activity}}}. At each level we have finalities {Second Law
{Maupertuis’ least energy {goal seeking}}}. The outermost class is locally
the weakest impulse, but it acts continuously and ‘fills in’ immediately
there is any hesitation, while the innermost subclass is the most
immediately effective, but its enthusiasms come and go, and do not last.
STAN
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