Random speculation about pronouns:

In most languages' system of pronouns, there are six basic forms -- the three persons, each with a singular and plural form. There may be some other divisions as well (often in the third person -- hän for people and se for non-people in Finnish, for example, or él and ella for masculine and feminine in Spanish). But some languages don't have the typical singular/plural divide -- ancient Greek has a little-known "dual" form, and highland Nepalese languages also have it, while I'm told Japanese has no plurals. And when you think about it, why if the difference between 1 and 2 so important as compared to 2 vs 3, or 40 vs 41?

Then there's the interesting divide made by Quechua in the first person plural -- noqancheq if it includes the person being spoken to, and noqayku if it doesn't. It seems like a more logical system would cover all the permutations of the three possible parties to a communication -- 1. the speaker(s), 2. the listener(s), and 3. other person(s).

So by this system, the pronouns would cover: 1, 1+2, 1+3, 1+2+3, 2, 2+3, 3. Or, in words: "just me," "me and you," "me and someone else," "me and you and someone else," "you," "you and someone else," and "someone else." A seven-slot system to replace the popular six-slot-with-modifications system.