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Re: [mathonweb] reminder: meetings this week

From: Volker Sorge <volker.sorge@gmail.com>
Date: Mon, 10 Sep 2018 18:55:00 +0100
Message-ID: <CAE5-06QSfPwt2FE5+yLtKTYMUKCr-HKrPfGgd=iWL8GtanU1PA@mail.gmail.com>
To: Neil Soiffer <soiffer@alum.mit.edu>
Cc: Peter Krautzberger <peter@krautzource.com>, mathonweb <public-mathonwebpages@w3.org>
There is no precedence order for logical and/or ∧/∨.
Precedence in classical logic is: negation over conjunction/disjunction
over (material) implication over equivalence.
You always need to disambiguate order of and/or.
Volker

On Mon, 10 Sep 2018 at 18:33, Neil Soiffer <soiffer@alum.mit.edu> wrote:

> Apologies for missing the meeting today -- I don't seem to have the
> meetings properly entered into my calendar and due to the time difference,
> I don't see Peter's reminders until after I start work.
>
> I have a question about what someone wrote on the Wiki:
>
>>      a∧b∨c it is not clear the order precedence. Usually ∧ has precedence
>> over ∨, but not always.
>>
>
> Can someone clarify (on the wiki) *when* it the normal precedence doesn't
> hold. What surprised me when I first looked into notations and precedence
> (20 years ago -- yikes!) was that although a symbols might have many
> different meanings, the precedence relationships it has didn't seem to
> change. I attributed that to people trying to avoid confusion when using
> familiar notation for new functionality. Having '∨' have a different
> precedence relative to '∧' in some cases seems very strange to me. But
> mathematicians do strange things at times (especially logicians ;-).
>
>     Neil
>
>
>
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>
> On Mon, Sep 10, 2018 at 12:36 AM, Peter Krautzberger <
> peter@krautzource.com> wrote:
>
>> Hi everyone,
>>
>> Just a quick reminder for the CG meetings this week.
>>
>> - a11y TF, Monday, Sept 10, 11am Eastern
>> - css TF, Monday, Sept 10, 12pm Eastern
>> - no CG meeting this week
>>
>> Best,
>> Peter.
>>
>
>
Received on Monday, 10 September 2018 17:55:34 UTC

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