Discussion of Homotopy Type Theory and Univalent Foundations
 help / color / mirror / Atom feed
From: Thorsten Altenkirch <Thorsten....@nottingham.ac.uk>
To: Steve Awodey <steve...@gmail.com>, Michael Shulman <shu...@sandiego.edu>
Cc: Stefan Monnier <mon...@iro.umontreal.ca>,
	"homotopyt...@googlegroups.com" <homotopyt...@googlegroups.com>
Subject: Re: [HoTT] "Identifications" ?
Date: Mon, 4 May 2020 16:17:00 +0000	[thread overview]
Message-ID: <D83C2B3E-AF61-409B-BE3A-A98839A00CF6@nottingham.ac.uk> (raw)
In-Reply-To: <E31B538B-E0C9-4D4F-A4F1-4335E59CAE0D@gmail.com>


    I’m afraid that someone may have hacked Thorsten’s email account. The real Thorsten went through all this with us many years ago. 
    : - )

One of our dogs gained access to my laptop - sorry. These animals can be very awkward.

However, even the real Thorsten had a friendly argument with Andre Joyal when we were writing the book about whether to use = for the equality type. 

Thorsten

On 04/05/2020, 17:08, "Steve Awodey" <steve...@gmail.com> wrote:

    I’m afraid that someone may have hacked Thorsten’s email account. The real Thorsten went through all this with us many years ago. 
    : - )


    > On May 4, 2020, at 12:00, Michael Shulman <shu...@sandiego.edu> wrote:
    > 
    > The word "path" is closely tied to the homotopy interpretation, and to
    > the classical perspective of oo-groupoids presented via topological
    > spaces, which has various problems.  This is particularly an issue in
    > cohesive type theory, where there is a separate "point-set level"
    > notion of path that it is important to distinguish from
    > identifications.
    > 
    >> On Mon, May 4, 2020 at 7:48 AM Stefan Monnier <mon...@iro.umontreal.ca> wrote:
    >> 
    >>> I don't think using "identification" necessarily implies any
    >>> difference between "identification" and "equality".  I don't think of
    >>> it that way.  For me the point is just to have a word that refers to
    >>> an *element* of an identity type.  Calling it "an equality" can have
    >>> the wrong connotation because classically, an equality is just a
    >>> proposition (or a true proposition), whereas an element of an identity
    >>> type carries information.  Calling it "an identification" suggests
    >>> exactly the information that it carries: a way of identifying two
    >>> things.
    >> 
    >> I thought that's what "path" was for?
    >> 
    >> 
    >>        Stefan "who really doesn't know what he's talking about"
    >> 
    > 
    > -- 
    > You received this message because you are subscribed to the Google Groups "Homotopy Type Theory" group.
    > To unsubscribe from this group and stop receiving emails from it, send an email to HomotopyT...@googlegroups.com.
    > To view this discussion on the web visit https://groups.google.com/d/msgid/HomotopyTypeTheory/CAOvivQx_2TinRHBrmOAZFnmFp8VVQ-yMcPvtKFtX-d9wGsD%2B2Q%40mail.gmail.com.




This message and any attachment are intended solely for the addressee
and may contain confidential information. If you have received this
message in error, please contact the sender and delete the email and
attachment. 

Any views or opinions expressed by the author of this email do not
necessarily reflect the views of the University of Nottingham. Email
communications with the University of Nottingham may be monitored 
where permitted by law.





  reply	other threads:[~2020-05-04 16:17 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-04  9:35 Thorsten Altenkirch
2020-05-04 10:59 ` [HoTT] " stre...
2020-05-04 11:04   ` Steve Awodey
2020-05-04 11:17   ` Thorsten Altenkirch
2020-05-04 11:42     ` Nicolai Kraus
2020-05-04 12:04       ` Thorsten Altenkirch
2020-05-04 12:06     ` Thomas Streicher
2020-05-04 12:12       ` Thorsten Altenkirch
2020-05-04 12:39         ` Thomas Streicher
2020-05-04 13:16 ` Michael Shulman
2020-05-04 14:17   ` Thorsten Altenkirch
2020-05-04 14:48   ` Stefan Monnier
2020-05-04 15:46     ` Nicolai Kraus
2020-05-04 15:57       ` Thorsten Altenkirch
2020-05-04 15:59     ` Michael Shulman
2020-05-04 16:07       ` Steve Awodey
2020-05-04 16:17         ` Thorsten Altenkirch [this message]
2020-05-04 16:53           ` Steve Awodey
2020-05-04 17:25             ` Thorsten Altenkirch
2020-05-04 17:43               ` Michael Shulman
2020-05-04 17:55               ` Steve Awodey
2020-05-04 16:21         ` Peter LeFanu Lumsdaine
2020-05-04 16:16       ` Joyal, André
2020-05-04 20:38         ` Joyal, André
2020-05-07 19:43 ` Martín Hötzel Escardó
2020-05-08 10:41   ` [HoTT] " Thorsten Altenkirch

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=D83C2B3E-AF61-409B-BE3A-A98839A00CF6@nottingham.ac.uk \
    --to="thorsten...."@nottingham.ac.uk \
    --cc="homotopyt..."@googlegroups.com \
    --cc="mon..."@iro.umontreal.ca \
    --cc="shu..."@sandiego.edu \
    --cc="steve..."@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).