From: Vaughan Pratt <pratt@cs.stanford.edu>
To: Categories <categories@mta.ca>
Subject: Re: "Historical terminology"
Date: Sun, 07 Oct 2007 17:12:36 -0700 [thread overview]
Message-ID: <E1IesQR-00047n-EG@mailserv.mta.ca> (raw)
JeanBenabou wrote:
> (i) Your "guess" about cartesian closed categories is most certainly
> correct. I knew that Eilenberg/Kelly had explicitly used this name
> in their La Jolla paper, and it is probably the first instance,
> because "closed", in this sense, was first introduced in that paper,
> as far as I know..
What most impressed my students and me two decades ago, when we were
applying the concepts of EK65 to modeling concurrency, was their attempt
to define "closed" as a self-contained notion independently of any
tensor product as its left adjoint (or so it seemed to us). This
defeated us. Has a clearer story of that attempt, or any related story,
emerged in the meantime?
> (iii) I agree with you on the idea that the "natural" definition of
> locally cartesian closed category should not imply the existence
> of a terminal object. If I asked the question, it is because in
> Johnstone's "Elephant" he does assume a terminal object. Has such an
> assumption become, now, commonly accepted in the definition ?
Hopefully not. If affine geometry has no origin, why should locally
cartesian closed categories have a global reference point? (What would
Andy Pitts have decided there, and for that matter the orientation of
profunctors in B2.7, which seems backwards from say Borceux?)
Vaughan
next reply other threads:[~2007-10-08 0:12 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-10-08 0:12 Vaughan Pratt [this message]
-- strict thread matches above, loose matches on Subject: below --
2007-10-08 18:18 Vaughan Pratt
2007-10-07 21:49 Prof. Peter Johnstone
2007-10-07 7:48 JeanBenabou
2007-10-05 14:52 JeanBenabou
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