- From: Volker Sorge <volker.sorge@gmail.com>
- Date: Mon, 10 Sep 2018 18:55:00 +0100
- To: Neil Soiffer <soiffer@alum.mit.edu>
- Cc: Peter Krautzberger <peter@krautzource.com>, mathonweb <public-mathonwebpages@w3.org>
- Message-ID: <CAE5-06QSfPwt2FE5+yLtKTYMUKCr-HKrPfGgd=iWL8GtanU1PA@mail.gmail.com>
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 > > > > <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free. > www.avg.com > <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> > <#m_5378311284654993367_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> > > 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