[cap-talk] Re: Question on web calculus - theoretical/practical

[Jed at Webstart]

At 08:42 AM 2/18/2006, David Hopwood wrote:
>Jed at Webstart wrote:
> > On 2/7/06, Olivier Lefevre <lefevrol at yahoo.com> wrote:
> >
> >> > > Tyler Close wrote:
> >> > > I built the Waterken Server toolkit to support developing
> >> > > capability-based applications. I have built some fairly large,
> >> > > security sensitive applications with it. [I showed] code
> >> > > fragments to the audience that proved the software implemented
> >> > > these guarantees.
> >> >
> >> > Still not a _theoretical_ analysis.
> >>
> >> Since you did not attend the presentation, your assertion is unsupported.
> >
> > Hmmm.  Is the above disagreement any more than a terminology issue?
> > I personally am more concerned with practical analysis than _theoretical_
> > analysis.
>
>It seems odd to me that anyone would assume /a priori/ that theoretical
>analysis is not also intended to be practical.
>
>"Theoretical" means something like "consistent with, and making use of a
>well-defined theory". "Practical" means something like "able to be put
>into practice". Where's the conflict here?

It seems a common enough connotation to me, e.g. from:

http://dict.die.net/theoretical/

      2: concerned with theories rather than their practical
         applications; "theoretical physics" [ant: applied]

or from:

http://www.answers.com/topic/theoretical

      2.  Restricted to theory; not practical: theoretical physics.
      3.  Given to theorizing; speculative.

though I admit that I do think "theoretical physics" is practical and
is not such a good example.  In my experience there is often
a distinction made between theory and practice.  For example in
theory one can use Quantum Mechanics to calculate the orbits
of electrons for any atoms.  In practice it's only possible to calculate
the orbits for the hydrogen atom and to make approximations for the
helium atom (at least last I checked).  For many years one could
say that in theory there should be three times the observed flux
of neutrinos coming from the Sun to the Earth.  That's a case where
they had to change the theory (mass for the neutrino and their
ability to change types).

Even in that call for papers that you just sent out the first sentence
is: "Computer security is an established field of computer science of both
theoretical and practical significance." - which would seem to antagonize
theory and practice.

It does seem a bit odd to me that Olivier Lefevre would
disparage the analysis that Tyler Close described by
saying that it wasn't a _theoretical_ analysis - apparently suggesting
as you (David H.) seem to feel that a 'theoretical' analysis is
based on a know theory and therefore better grounded or more
sound - while at the same time I can interpret a 'theoretical'
analysis to be less useful because it is only 'theoretical' and
not necessarily practical.

Whether or not one considers the word "theoretical" to be
appropriately applied to an analysis of capability flow, I have
experience with practical application of such an analysis,
so I think I side with Tyler on the pragmatic issue of the
value of the 'web calculus' (though I may not be using that
term in exactly the sense Tyler would prefer/demand).

--Jed http://www.webstart.com/jed/