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From: Thomas Streicher <streicher@mathematik.tu-darmstadt.de>
To: Andrej Bauer <andrej.bauer@andrej.com>
Cc: categories list <categories@mta.ca>
Subject: Re: A category internal to itself
Date: Fri, 6 Sep 2013 14:33:37 +0200	[thread overview]
Message-ID: <E1VHvsJ-0000yO-62@mlist.mta.ca> (raw)
In-Reply-To: <CAB0nkh3zxgAV4tU1jr5ZTWw0exgQEcjGVSyRDqy=T0XE6DaG6Q@mail.gmail.com>

> The results would be a model of type theory (with ?? and ?? but no Id)
> which models Type : Type. It is not trivial, but all types are
> inhabited (and have the fixed-point property). We can still interpret
> Girard's paradox in it, but it is not really a paradox without
> identity types as the type structure does not collapse. Has something
> like that known? (I fully expect Thomas to pull something out of his
> beard.)

Indeed this was done in the Thesis of Nancy J. McCracken in 1979
supervised by John Reynolds. Its title is

   An investigation of programming languages with a polymorphic type
   structure.

Cardelli and Wegner got interested in this in the mid 1980s. There are
2 paper on this one can find on the web

Cardelli & Wegner  On Understanding Types Data Abstraction and Polymorphism
                    Computing Surveys, Vol.17 (1985)

Cardelli  A Polymorphic Lambda Calculus with Type:Type
           a DEC report from 1986

That's what I have wrung out of my beard
Thomas


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  parent reply	other threads:[~2013-09-06 12:33 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-04  9:23 Andrej Bauer
2013-09-04 20:04 ` Eduardo J. Dubuc
2013-09-04 22:11 ` Colin McLarty
2013-09-05  8:27 ` Edmund Robinson
2013-09-05 11:30 ` Zhen Lin Low
2013-09-05 13:44   ` Alex Simpson
     [not found]   ` <20130906080410.GA19753@mathematik.tu-darmstadt.de>
2013-09-06  8:20     ` Zhen Lin Low
     [not found]   ` <CAB0nkh3zxgAV4tU1jr5ZTWw0exgQEcjGVSyRDqy=T0XE6DaG6Q@mail.gmail.com>
2013-09-06 12:33     ` Thomas Streicher [this message]
     [not found] ` <CAOzx82rUa8KRkngePON8Gh1KttzZ1-3AKNpP5DQNY7RfEj1VTQ@mail.gmail.com>
2013-09-05 11:46   ` Colin McLarty
     [not found] ` <CAOOzEh-04Cq7L_k7v6qxWTYRhkWZw862kmPzLaSNZUgr8Zvzdw@mail.gmail.com>
2013-09-06  9:48   ` Andrej Bauer

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