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From: Toby Bartels <toby+categories@ugcs.caltech.edu>
To: categories@mta.ca
Subject: Re: Cartesian closed without products
Date: Mon, 7 Jan 2008 13:35:11 -0800	[thread overview]
Message-ID: <E1JCJ0o-0005w1-Sb@mailserv.mta.ca> (raw)

Richard Garner wrote:

>On reflection, [...]
>EK-closed requires the unit object to be representable as
>well.

This is a reasonable requirement anyway,
since the unit is the 0fold iterated hom,
just as it's the 0fold iterated product.
So if you think <closed under binary products>
should be accompanied by <with a unit object>,
then so should <closed under internal homs>.

OTOH, the version without unit probably has some use,
just as non-monoid semigroups occasionally do.


--Toby




             reply	other threads:[~2008-01-07 21:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-07 21:35 Toby Bartels [this message]
  -- strict thread matches above, loose matches on Subject: below --
2008-01-09  2:29 Toby Bartels
2008-01-09  1:36 Peter Selinger
2008-01-08 21:29 Ronnie
2008-01-07 14:09 Richard Garner
2008-01-07 11:08 Richard Garner

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