Glen -
Cherry picking here...
I actually distrust consensus and convergence, equally, I think. This
is for the same reason I think the "singularity" concept is suspicious.
It implies a closedness that I don't believe in. The universe seems
open to me, which implies that any process (including explanation)
_wanders_ significantly. I will admit constraints, though. Although
any process may wander, it may do so within some hard boundaries ...
like a sandwiched series that forever oscillates without actually
converging.
I recently started a project which involves Quorum Sensing in the
cell-cell signaling sense. I presume your beef with consensus
(especially) and convergence (maybe less so) is the implied finality or
totality of it? I presume you will agree that there are 'degrees' of
recruitment that might lead to a quorum (and in the extreme a
consensus?) and in entrainment as a form of recruitment?
For most of my career, I've tried to explain to my fellow simulants
that any particular snapshot of a modeling effort is not very useful.
I.e. any particular _model_ is not very useful (with an
anti-authoritarian prejudice against the much-abused "all models are
wrong, some are useful" aphorism -- I actually think that aphorism has
done more damage to the proper way to use simulation than any other
concept).
This is an aside I'd like to try to untangle a little: The aphorism in
question is, for me, an antidote to two extremes. One extreme of
course, is the one where some people harp on the problems in a model to
the extent of not appreciating that they are not by definition anything
*but* a model, the finger pointing at the moon, the map which is not the
territory (aphorismia ad nausea)... the other extreme is the one where
some (other) people imagine that (usually their own) models are reality
or more than "useful" in a given context (some kind of blessed state as
a chosen or special model?).
I assume you are not quibbling with those two uses of the aphorism? But
more (maybe) with the nature of aphorisms (similar to the problems with
models... trying to claim a universal truth?).
A simple summary might just be an explanation of how you think this
aphorism has "done more harm..." ? I'm sure it *has* done harm, but
I'm not sure what it is you refer to?
But the whole modeling and simulation (M&S) effort (trajectory or bundle
of trajectories, given model forking) _is_ useful.
I worked on a project back around the turn of the century (I find that
phrase entertaining, especially now that it is as relevant as it was to
my Grandfather as he trundled off to WWI in 1918) which was a
"composable simulation" framework. The prime example we used it on was
for the Future Combat System (misbegotten/ill-fated? DoD project) where
we applied something we dubbed as "generative analysis" to explore a
subset of model-space via iterated simulation using a
learning-classifier system (roughly a GA) to speciate and test the
results. In this case, there was a single meta-model which was that
Red Team and Blue Team forces could be conjured with a wide range of
features within the meta-model's trade-space (range, speed, firepower,
armor, comms, sensors, etc.) and pitted against eachother.
Specifically, we would set up hundreds of Blue-Team compositions and run
them against a fixed red-team composition and initial conditions, etc.,
obtain a multivariate effectivity function (mission success, Blue Loss,
Red Loss, residual capability, etc.) to use to evaluate and spawn a new
population, etc.
I assume this is a (constrained?) variant of what you are calling
"model-forking"? "trajectories" would seem to relate to varying initial
conditions or boundary constraints to generate ensembles of results from
a "single?" model?
In other words, iteration is "doing it again" and recursion is "doing it
to the result of the last time you did it", making recursion more
specific. Hence, recursion targets a more closed type chain.
This is important to me because my work is multi-formalism, the model
produced in one iteration can be wildly different from the model
produced in prior or subsequent iterations, different in generating
structure and dynamics as well as phenomenal attributes.
Hence I like the concept of filter explanations better than that of
recursive explanations, where the filter can co-evolve with the stuff
being filtered.
I'd like to catch up on your definitions here (in this thread or our
offline parallel one)... maybe others are curious as well by what you
mean by multi-formalism and these evolving models (My example with
GA-designed ensembles of meta-model parameters might be the same thing
roughly?).
Thanks. I've added it to my Powell's wishlist.
You lucky boy, to live within a drive or rail to Powells on demand. My
wife and I spend up to half our time there it seems when we visit the
area. The independents are going slowly but surely. Powells is a bastion.
I wonder if Dymocks "down under" is still viable? I believe we have a
few Ozzies (and maybe a Kiwi or two?) here... I know anecdotally they
are still alive, but with Amazon Worldwide and the changes(?) in the
Commonwealth's practice around protecting it's own publishing industry,
I suspect their niche has changed radically?
- Steve
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