Commentary on Wittgenstein's Philosophical Investigations
First off, I find Wittgenstein's use of multiple voices easy to read because I myself use multiple voices all the time when I am thinking. I may think a thought, then respond to it from another perspective. It is like hearing two people talk, except you identify as both of them at the same time. And that is what passes for my stream of consciousness. Actually, I do have voices that I consider to be myself, and those which I consider to be my impressions of other people. And of course not all my thought is verbal!
Wittgenstein seemed to be saying that language (and by extension, logic and thought) are all very relative. The meaning of language depends on the context. There always must be a context. For example, wondering what the parts are of some object only makes sense if you have some context within which to ask the question. The fundamental parts of, say, a tree, are different depending on what kind of answer you want. You might say that the basic parts are the branches, or maybe the cells, or the atoms that constitute the tree. Another situation where meaning depends on context is in the case of metaphors and words with multiple meanings. You can only know what the word refers to from the context. There is not a special essence for each word to refer to. So there is no perfectly exact language which is free from the necessity of an arbitrary environment to give it meaning.
The implication of this is that language is not so special as is commonly believed. Language can not be understood as a perfectly exact mathematical manipulation of symbols. Instead it is rather chaotically interpreted based on preconceptions and context, obeying no particular law. In this way it is similar to the other activities of the brain - chaotic and messy, but also creative. Another interesting point is that the brain can learn a language without having any prior understanding of it. What Wittgenstein tries to show in the beginning of his Philosophical Investigations is that it is not possible to explain in a purely algorithmic way how language is learned. Discussing language requires understanding of self-organizing and evolving systems, and not of sequential, logical systems. So then language becomes not the vehicle for an ultimate truth, or something with which to distinguish between rational and irrational beings, but just another technique of evolutionary systems. Language has a role to play, but it does not live separately from a natural understanding of the world.