Jerry, List,

I'm not exactly sure how to answer your question (I'm assuming that it's
about the parenthetical comment).

Sheaf theory, which appears to be changing to some consideral extent the
direction of topological mathematics, uses such concepts as presheaves
being *glued* together. Honestly, although I attended 3 of Fernando's 6
lectures (which included discussions of sheaf theory) at Pratt in NYC this
Fall, *that *mathematics was very far 'above my pay grade'. Although I
followed a lot of it and learned a lot, I was principally interested in
Fernando's insights into Peircean pragmatism and the continuum as Peirce
understood it.

For those who aren't familiar with sheaf theory, a sheaf is defined as "a
tool for systematically tracking locally defined data attached to the open
sets <https://en.wikipedia.org/wiki/Open_set> of a topological space
<https://en.wikipedia.org/wiki/Topological_space>."   Two wikipedia
articles are helpful for the novice, one on Grothendieck's work (which was
the topic of Fernando's seminar series):
https://en.wikipedia.org/wiki/Grothendieck_topology

and a more general one. Perhaps this snippet from the latter site will show
why I commented that 'glue' was a technical term in this mathematics.

. . . A presheaf is *separated* if its sections are "locally determined":
whenever two sections over *U* coincide when restricted to each of *V**i*,
the two sections are identical. . .  Finally, a separated presheaf is a
*sheaf* if *compatible sections can be glued together*, i.e., whenever
there is a section of the presheaf over each of the covering sets *V**i*,
chosen so that they match on the overlaps of the covering sets, these
sections correspond to a (unique) section on *U*, of which they are
restrictions.
https://en.wikipedia.org/wiki/Sheaf_(mathematics)

But, again, my ignorance of this mathematics is profound.aeven though I've
been self-studying topology for some time now.

Best,

Gary R


[image: Gary Richmond]

*Gary Richmond*
*Philosophy and Critical Thinking*
*Communication Studies*
*LaGuardia College of the City University of New York*
*C 745*
*718 482-5690*

On Tue, Dec 1, 2015 at 12:51 AM, Jerry LR Chandler <[email protected]
> wrote:

> Gary:
> On Nov 30, 2015, at 11:02 PM, Gary Richmond wrote:
>
> And he quotes Peirce, from several sources, in support of this notion (I
> should note, btw, that "glues" in the passage above is a technical term in
> the mathematics which Zalamea espouses).
>
>
> I am curious as to why you consider this assertion valid.
>
> Cheers
>
> jerry
>
>
>
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