University of Calgary
UofC Navigation

Strict Conditional in LaTeX

This website has moved!

You are looking at an archived page. The website has moved to

Submitted by Richard Zach on Wed, 02/14/2007 - 2:42am

I just had occasion to have to typeset Lewis's strict conditional symbol in LaTeX. It turns out it isn't in the standard AMS fonts. Peter Smith's LaTeX for Logicians to the rescue! There I found:

  1. that the strict conditional symbol is in the fonts that are part of the txfonts and pxfonts packages, and
  2. that there is a wonderful 110 page/3 MB comprehensive listing of all LaTeX symbols (by Scott Pakin).

Now it turns out that the point of txfonts and pxfonts is to give you output in Times Roman and Palatino fonts, respectively, with matching math and symbol fonts. That's useful in itself--but if you happen to not want your document to be in Times or Palatino, you can still get \strictif by putting this in the preamble:



Submitted by lumpy pea coat on Wed, 02/14/2007 - 6:30pm

Good to know!

Submitted by Anonymous on Sat, 02/17/2007 - 8:35pm

That's helpful! Is there a similar trick for typesetting the `box arrow' symbol that is sometimes used for the counterfactual conditional? I think it's called `\boxright' in pxfonts/txfonts.

Submitted by Richard Zach on Sat, 02/17/2007 - 11:44pm

Just look up the font and symbol declarations in txfonts.sty:\DeclareMathSymbol{\boxright}{\mathrel}{symbolsC}{128}

Submitted by Peter Smith on Thu, 02/22/2007 - 9:01pm

I've added (with acknowledgement!) your code for using symbols extracted from txfonts to LaTeX for Logicians. Thanks for that!

Submitted by google on Mon, 07/30/2007 - 1:08pm


Submitted by Anonymous on Sun, 12/20/2009 - 6:44pm

Great! Any thoughts on how to do this for use with XeLaTeX instead? Thanks!

Submitted by Delia on Sun, 02/08/2015 - 5:21pm

Thanks, Richard! By the way, your link to "Peter Smith's LaTeX for Logicians" is dead.

Submitted by Richard Zach on Sun, 02/08/2015 - 6:27pm

Fixed, thanks.