RE: superscript π?

Doug Ewell doug at
Mon Aug 2 00:09:00 CDT 2021

Although the Unicode Technical Committee has stated many, many times that additional superscript and subscript letters will not be encoded, except to support natural-language orthographies and phonetic notation, it’s impossible to predict whether that principle will be upheld forever. We do have things in Unicode today that were once "no, not ever" and some that appeared as a Notice of Non-Approval.

What is certain, however, is that no character will be added based solely on a public mailing-list thread. A formal proposal must be submitted. Even new emoji base characters require a submitted proposal, though it's quite different from that required for normal characters. Perhaps by "I'm requesting" you meant you wanted to open discussion and build evidence and support on the public list before preparing your proposal.

More comments below.

David Chmelik wrote:

> There are several other Greek superscripts, so I'm again requesting a
> superscript π (pi, Greek letter p.)

The existence of other superscripts in Unicode is not precedence on its own for encoding others. Each must be justified individually.

> The previous argument that mathematics discussion should be in complex
> document formatted text (TeX, etc.) is false.

Simply asserting that a given argument is "false" usually isn’t a great argumentative strategy and is unlikely to convince those who support that argument. "Oh, I'm wrong? Very well, then, I'm wrong. Sorry."

> There has always been, and still is, mathematics discussion in plain-
> text only, such as on NNTP/Usenet (and Gmane) and Internet Relay Chat
> (IRC) some of which still have very large science discussion areas.

Are you aware of Unicode Technical Report #25, "Unicode Support for Mathematics"? This was prepared, and revised many times, with quite a bit of input and support from the mathematical community. It provides a way to represent math notation, using the Unicode characters that currently exist, that is recognized and accepted by mathematicians.

> You should probably even have complete English and Greek superscripts
> & subscripts.

You may not realize how much this statement torpedoes your basic argument for encoding superscript π. "Let's encode all of them" is exactly the floodgate Unicode is trying to avoid opening.

> That doesn't mean it's necessary to have further levels of
> superscripts and subscripts because in such less-common cases there is
> notation for that.

But math does require arbitrary levels of superscripting and subscripting, as well as much more two-dimensional layout. So a great deal of math notation would still not be representable in plain text. Some already is, and has been long before Unicode: x² + y² = z². Adding another superscript character doesn't make math notation available in plain text in general; it just moves the have/have-not bar a little.

Doug Ewell, CC, ALB | Lakewood, CO, US |

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