On 10 Sep 2013, at 21:04, Asmus Freytag <[email protected]> wrote:
> On 9/10/2013 11:05 AM, Michael Everson wrote: >> On 10 Sep 2013, at 18:01, Asmus Freytag <[email protected]> wrote: >> >>> This rationale is absent in document WG2 N3907 that requests these >>> characters. >>> >>> Therefore, it seems these two additions should not have been made. >> I disagree. The mathematical characters are not proper letters, but are >> symbols used in mathematics; the letters for German dialectology are no >> different in principle from the insular letters also encoded for linguistic >> purposes. > > This doesn't pass the smell test. > > Ask any mathematician whether these are "letters" and the answer is "yes". > > They are letters used in mathematical or physical formulae, that doesn't make > them symbols, … They can be used as both, in compounds like the function name "sin", where they clearly function as letters, though not common for Fraktur, which is mainly used for Lie algebras, and as single letters, where they function as symbols. Some symbols evolve and become clearly separate from their original letters. For example, the integral sign ∫ is originally an "S", introduced by Leibnitz. The symbol for the empty set ∅ is originally a Greek letter phi ϕ, ans some use the latter. Also, my dictionary says that Fraktur is a German style of black-letter type. It probably came from the use by German mathematicians; Hermann Weyl introduced Lie algebras in the 1930s.
