[linux-elitists] git and a sysadmin book

Jeremy Hankins nowan@nowan.org
Fri Jan 16 19:57:03 PST 2009


Rick Moen <rick@linuxmafia.com> writes:

> You would be a case in point: Your nit was explicitly feedback
> advising Karsten about the technical meaning of "entropy" (and it
> seemed you likely assumed the physics meaning to be the only such
> technical sense), in _distinction_ to what Karsten said.

I'm not sure where I gave the impression I was concerned with the
physics definition; that certainly wasn't my intention.  My nit (i.e.,
to replace "low entropy pools" with "dependency on low entropy pools")
was intended to eliminate a conceptual confusion.  Not a confusion fatal
to Karsten's rule of thumb, but a genuine confusion none the less.

Under the notion of entropy Karsten was using something can be low
entropy only if it also has high potential, where this essentially means
anything with big possible consequences (e.g., words transposed in a
presidential address).  There's an implicit dependency claim in there
that I think is important for Karsten's point, but it's very difficult
to explain using this set of concepts.

If we understand entropy as not necessarily including high potential I
can say: what matters is that the preservation and/or prevention of the
high potential _depends on_ the low entropy pool.  But if entropy and
potential are mushed together that sentence is gibberish.  As you say,
it's probably clear to anyone who thinks about it for a minute.  But
saying it explicitly is of benefit, and using concepts which make it
impossible to say can lead to confusion.

> So, you clearly weren't the least bit confused as to what Karsten
> meant.  Nick Moffitt wasn't.  I wasn't.  Who was?
>
> You have a valid point that Karsten was being a bit murky in mashing
> together (in his rule of thumb) order/entropy and (potential) energy
> or stasis.  I think any halfway attentive reader of his dictum will
> notice that he's doing so.  But that's not confusion.

Hmm, I may be guilty of a bit of confusion here: by "conceptual
confusion" I meant something very specific and distinct from confusion
proper -- I was certainly not accusing anyone of being confused.  Mea
culpa, I was probably lapsing into philosophy-speak.  But that said, I
did have to reread the original post a couple of times to make sense of
it.

> If this _were_ in context of physics, the carefree murkiness of
> Karsten's appeal to pop science would be a problem.  But it isn't --
> and the general-discussion concept of entropy isn't the same, and
> won't gain rigour by waving the spirit of Feynmann at it.

Murkiness of concepts isn't something we don't have to worry about
unless we're physicists, nor is it something physicists (even good ones)
are immune to.  Most of the time it doesn't matter, even for physicists.
Conceptual clarity matters just insofar as it affects what you're trying
to say.  In the case of Karsten's rule of thumb I think it does affect
what he's trying to say, though not egregiously.

-- 
Jeremy Hankins <nowan@nowan.org>
PGP fingerprint: 748F 4D16 538E 75D6 8333  9E10 D212 B5ED 37D0 0A03


More information about the linux-elitists mailing list