[SCL] two comments

[Murray Altheim]

John F. Sowa wrote:
> Murray, Tanel, et al.,
> 
> The distinction between an abstract and a concrete syntax
> is a very precise, formal distinction.  There is no such
> thing as multiple levels of this distinction.  The basic
> idea is that all semantic definitions are stated in terms
> of an abstract syntax, which is not printable, and that same
> abstract syntax can be realized in multiple concrete forms.

John,

Spoken with true conviction. But I guess we'll have to agree to
disagree. You can certainly *define* this the way you like, just
as McCarthy has, but these distinctions exist only within the
constraints of a system designed to support and requiring of such
distinctions. In order for that system to work, you must have that
belief, so you do. I prefer to move forward with a different
conviction, that while some people may believe that there are
precise, formal distinctions, this is all a matter of language, the
communication of concepts, part and parcel of the limits of human
understanding, and that the distinctions made are not found in
reality itself, that "abstract" and "concrete" are merely labels
for two poles of a continuum. The question for me is not whether
it is a continuum, but whether one can grasp either pole.

Turtles, turtles, turtles, all the way down...

Murray

...........................................................................
Murray Altheim                         http://kmi.open.ac.uk/people/murray/
Knowledge Media Institute
The Open University, Milton Keynes, Bucks, MK7 6AA, UK                    .

   Stephen Hawking's A Brief History of Time tells the story of a
   cosmologist whose speech is interrupted by a little old lady who
   informs him that the universe rests on the back of a turtle. "Ah,
   yes, madame," the scientist replies, "but what does the turtle
   rest on?" The old lady shoots back: "You can't trick me, young man.
   It's nothing but turtles, turtles, turtles, all the way down."