Talk:Table of logic symbols

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Contents

[edit] Re. to math table

This page is a trimmed version of Table of mathematical symbols. -Chira 15:46, 20 August 2005 (UTC)

We should add a few more operators here, in particular modalities, strict implication, and maybe the operators from linear logic. --- Charles Stewart 20:10, 23 August 2005 (UTC)
Do you see this table developing independently of Table of mathematical symbols? Paul August ☎ 21:59, August 31, 2005 (UTC)
What are the origin of the THEREFORE and BECAUSE signs? The three-dot triangles I mean. Evertype 15:41, 14 September 2005 (UTC)
I hope somebody can answer that last point. I was trying to find out which character sets support the "therefore" symbol, and found it doesn't seem to be mentioned anywhere in Wikipedia – at least not anywhere obvious or findable by using the search tool on "therefore symbol". – Kieran T (talk | contribs) 14:18, 23 July 2006 (UTC)
P.S. The W3C has come to my rescue revealing that ∴ is ∴. Would still like to see its etymology documented in WP somewhere though. – Kieran T (talk | contribs) 14:23, 23 July 2006 (UTC)

The turnstile ("|-") symbols should be included here.

[edit] Regarding the Logic Symbols

To take care of the problem with the symbol fonts displaying differently on different browsers, why not make the symbols into image files? This would ensure that everyone (regardless of their browser) can view the symbols. I find it difficult to understand the logic of having a logic table that you may or may not be viewing properly. 64.95.214.18 17:46, 20 December 2005 (UTC)Anonymous

[edit] Overscore

'Twould be nice to include the overscore as a way of indicating logical negation/complementation. —12.72.71.7 12:50, 27 July 2006 (UTC)

[edit] Incomplete

This article's listing of logic symbols is incomplete. I noticed that a while back, but I was too lazy to fix it. I'll fix it now. Robocracy 11:46, 22 October 2006 (UTC)

There are still plenty of things to add/change. The triple bar is far more commonly used to indicate material equivalence than to indicate definition (if it does the latter ever). The equals sign is commonly used for strict equivalence. Double turnstile is missing. It should be noted that – is sometimes used as negation, and . is sometimes used as conjunction (but also periods are used to serve the same purpose as parentheses sometimes). Then there are, of course, the modal operators including the box (necessary, obligatory) and the diamond (possible, permissible) and the fishhook (strict implication). Philosophers also often use the set membership, intersection, and union symbols. Also the slashed equals sign, turnstile, double turnstile and set membership symbols are used to indicate the negation of those relations. Then if we really wanted to get crazy, we could include even rarer things like the Sheffer stroke, corner quotes or the substitutional quantifier. (I'd fix most of this right now, but tables annoy me and I don't have the patience to figure this one out at the present moment.) KSchutte 21:20, 3 April 2007 (UTC)
Also, the therefore symbol mentioned above on this very talk page still isn't included on the table. KSchutte 21:21, 3 April 2007 (UTC)

[edit] Ordinary name for each sign

Two things. First, why not add each symbol ordinary name, the only one I know is the tilde "~", but I am sure they have ordinary names. Second, how about including the schefferstroke? Or should we change the article to be about the logical symbols only in propositional and quantified logic? RickardV 06:58, 30 April 2007 (UTC)

[edit] inference section... mistake?

"x ⊢ y means y is derived from x." According to the definition on the page, shouldn't it be x is derived from y? Springbreak04 23:45, 26 June 2007 (UTC)

x ⊢ y means "y is a syntactic consequence of x," or "from x we can derive y"

Gregbard 12:22, 23 July 2007 (UTC)

[edit] Symbols should appear in mathtype format

I cannot read many symbols, and I giess I'm not the only one. I think it's better to write them in mathtype format: <math>Insert non-formatted text here</math>. Please anyone who CAN read the symbols, do it. Dan Gluck 19:45, 23 August 2007 (UTC)

[edit] "And"

I don't know how to edit the table, but someone might note that the dot is often used for "and" (e.g in Copi). Carolynparrishfan (talk) 22:04, 24 November 2007 (UTC)