# Re: Binary Relations, draft 1

• To: Thierry Bouche <Thierry.Bouche@ujf-grenoble.fr>
• Subject: Re: Binary Relations, draft 1
• From: Hans Aberg <haberg@matematik.su.se>
• Date: Wed, 18 Nov 1998 13:09:08 +0100
• Cc: math-font-discuss@cogs.susx.ac.uk
• Content-Length: 1115

```At 11:31 +0100 1998/11/18, Thierry Bouche wrote:
>But, with H. Aberg's rule, we would have to distinguish between:
>
> Let \$f\$ be a continuous function (math ital)
>
>and
>
> Let \$f(x)=\exp(x^2)\$  (f should be upright, as it will be of constant
>meaning thereafter, whereas x should me math ital)

Even though this is not what I meant: The "constantness" of the names
should go beyond the local formula and the paper and be more universally
accepted -- but it is still up the the every author to interpret what this
means.

So I think that both \$f\$ above should be typeset in italics. However, the
imaginary unit i should be typeset upright. Then one can distinguish this
"i" from a summation index.

Otherwise, I just tried to describe what might be an underlying semantic
principle (as opposed to principles govern by graphical concerns): My idea
is not to enforce or impose this onto others.

Hans Aberg
* Email: Hans Aberg <mailto:haberg@member.ams.org>