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""" there are characters with no glyphs. glyphs that can correspond to a number of different characters according to context. Glyphs that correspond to multiple characters at the same time (with weightings assigned to each), and even more possibilities.
The problem of glyphs and characters is so complex that it has gone beyond the realm of computer specialists and has come to be of interest even to philosophers. For example, the Japanese philosopher Shigeki Moro, who has worked with ideographic characters in Buddhist documents, goes so far in his article Surface or Essence: Beyond Character Model Set [274] as to say that Unicode's approach is Aristotelian essentialist and to recommend supplanting it by an approach inspired by Jacques Derrida's theory of writing [114, 115]. The reader interested in the philosophical aspects of the issue is invited to consult [165,156], in addition to the works cited above. """
I think "essentialist" is probably a good description of the philosophy of how Unicode defines characters as opposed to fonts and glyphs, so I adopted it.
(Arguably even in English we run into the fact that there is not one "A" - there are many "A"s that sound and act completely different, and we collapsed them into one representation.)
Which is always fun when you think that clearly nobody thinks of "o or o with a leg" (O vs Q).