From: glenn@wheat-chex.ai.mit.edu (Glenn A. Adams)
Newsgroups: comp.std.internat
Subject: Re: Script Unification [was: Re: Cleanicode]
Date: 23 Jan 1993 17:37:01 GMT
Organization: MIT Artificial Intelligence Laboratory
NNTP-Posting-Host: wheat-chex.ai.mit.edu

In article <ISHIKAWA.93Jan22203618@ds5200.personal-media.co.jp> ishikawa@personal-media.co.jp writes:

>>Of course it is true that CJK unification does have certain costs,
>>e.g., different implicit sort orders cannot be maintained without
>>language tags, minor distinctions in the glyphic representation of
>>CJK character data cannot be made without language tags, and so
>>forth.  However, and this is important to consider, such distinctions
>>are not maintained by character set standards practices for other
>>scripts either:  the English, German, French, and Spanish alphabets,
>>all distinct in their ordering rules, all potentially requiring slightly
>>different glyphic displays, 

>But, here is the dumb question. Are 'a', 'b', 'c' in English and, say,
>the similar looking characters in French given slightly different
>glyphic display under similar circumstances?!

My point in this paragraph is that existing character sets like ISO8859-1
(IsoLatin1), or the Windows ANSI set, or the standard Apple set, do
not distinguish among the symbols which are shared by different alphabets
which are derived from the Latin script.  Unifying these alphabets as
a single alphabet-independent script makes a lot of sense for many kinds
of text processes, e.g., searching, yet makes other processes difficult,
e.g., culturally correct sorting.  As for display, simple display systems
will probably never distinguish among the forms used to display these
alphabets; however, high quality typography may very well abide to
different standards as to which font to use to display these different
alphabets usage of a single script.  This is similar to the situation
in CJK:  different alphabets' use of the Han script (here I am thinking
of Traditional Chinese, Simplified Chinese, Japanese, and Korean as
four distinct alphabets) requires different fonts for quality display;
yet for simple, legible display, one font will suffice.

One argument that has been made against Han unification is that these
different uses require different display forms.  But the differences
in form are minor and do not affect the meaning of the text.  This
is identical to what holds in unifying different alphabets which use
the Latin script.  Admittedly, there are many more forms in the Han
script, and, given the complexity of these forms, there is much more
opportunity for variation.  However, these variations do not in general
cause a change in the meaning (basic content) of the text.  The goal
of Unicode was to define a "plain text format" which captured only
the basic content and no more; any further distinctions, such as font
attributes or language attributes, are expected to be subsumed in
some rich text form which is layered on top of (or interleaved with)
the basic Unicode plain text string.

Your basic Unix terminal emulator or text editor can deal with 
Unicode plain text just like ASCII or JIS plain text (with the
appropriate modifications for 16-bit characters).  Legibility is
insured by the criteria of Unicode plain text.  On the other hand,
a desk top publishing system or a more advanced word processor will
most certainly support font attribution, and, in a multilingual
environment, language attribution.  If you look at programs like
Interleaf and Slate (a multimedia editor from BB&N), they have
supported language attributes in their rich text format for a
long time now.

Glenn Adams