At some point after our Tractatus episodes came out, Sean Wilson, a political science professor at Wright State University, contacted me to find out when we'd be doing the Investigations so as to coordinate something between us and his discussion group.
Some years later now, I've checked out his forum: "Wittgenstein's Aftermath: Life in the Post-Analytic World, Given by the Man Who Ended Philosophy As History Knew It."
The forum is not very active right now, but there's an archive of decent discussion with many links if you'd like to know more about Wittgenstein on language, mind religion, mathematics; about Wittgenstein's personal life; or if you'd like to talk more about the Tractatus, this might be a good place to look.
Here is part of a conversation there concerning one of the issues PEL has been tackling which maybe you commenters can continue here:
§43 of the Investigations famously says:
"For a large class of cases of the employment of the word 'meaning' - though not for all - this word can be explained in this way: the meaning of the word is its use in the language. And the meaning of a name is sometimes explained by pointing to its bearer."
The caveat in this passage ("though not for all") has always intrigued me. Which class - or classes - of cases might Wittgenstein have wanted to exclude? Of course, he gives an example of one such class at the end: pointing to the bearer of a name. But are there any others you can think of?
... there's only one of three answers.
1. The point at which meaning isn't use is simply the point where the use doesn't create meaning (if that's possible); or where, better yet, it does not create successful meaning.
2. He speaks of words that do not develop more than one sense in the language culture, because of the way those words are socially policed. It is possible that certain kinds of scientific jargon work like this. If more than one sense cannot develop for any word, meaning seems fixed.
3. It's an unfortunate passage that didn't get cleaned up in a book that he never got to the point of being "finished." You'd have to be able to square it with everything else he said and wrote in that period. So if meaning isn't use for some things, those things sure are rather limited.