More or less corresponding to the fact that we can write up any number in binary notation (if we use enough digits), since there are:
We can map out any number of characters in a system and still maintain a degree of completeness.
For example, if a written language has 43 characters, we can associate pentagrams, trigrams, monograms and the zerogram with them:
43 = 32 + 8 + 2 + 1
In the traditional I Ching system, we use either trigrams or hexagrams; either of these are a complete level of their own.
However, we can relate any of these levels to other levels simply by adding or removing lines from a gram; we can make a 'level jump' very easily.
In a language with set characters (where all characters are 'equal'), 'jumping levels' is not intrinsic to notation, and it would have to be mapped in to the meaning of characters.
By mapping several complete levels corresponding to layers of the I Ching system, language/magical systems with set characters too can maintain flexibility and more levels of completeness.