How Many Common, Unique Letters Do *You* Think There Are?

[Rafal]

None: glyphs are not letters. Calling them letters presupposes a simple substitution is possible.

[pedant mode]
Yes, not every writing system contains letters. Chinese signs aren't letters.
But if Voynichese glyphs are not letters then EVA shouldn't be called an alphabet  

You are not allowed to view links. Register or Login to view.
An alphabet is a writing system that uses a standard set of symbols, called letters, to more or less represent particular sounds in a spoken language
[/pedant mode]