Philosophical Investigations, reading it together. I feel as though I've fallen behind, but things are getting serious (and more difficult) now. I've also spent a little longer on §50 to try and get clear in my own thinking.
§49. What does it mean "to say that we cannot define (that is, describe) these elements, but only name them?" Referring to his example of the 3x3 colour matrix at §48, W proposes the "limiting case" of a (one square) 1x1 matrix having a definition or description that is "simply the name of the coloured square". He states that "a sign "R" or "B", etc. may be sometimes a word and sometimes a proposition. But where it 'is a word or a proposition' depends on the situation in which it is uttered or written." W states that the word "R" might be a description or a proposition if it is being used within a language-game to refer to a coloured square. Alternatively, the same word "R" might be a word or a name if its use is being taught to others or to oneself, and where it is, therefore, only being prepared for use within a language-game. As Wittgenstein states:"...naming and describing do not stand on the same level: naming is a preparation for description. Naming is so far not a move in the language-game..."
§50. "What does it mean to say that we can attribute neither being nor non-being to elements? One might say: if everything that we call "being" and "non-being" consists in the existence and non-existence of connexions between elements, it makes no sense to speak of an element's being (non-being)..."
That is, if being (and non-being) consists in (or is defined as) the connections between elements, then it makes no sense to speak of the being (or non-being) of the elements themselves. This is clarified by his next statement:
"...just as when everything that we call "destruction" lies in the separation of elements, it makes no sense to speak of the destruction of an element..."
That is, if destruction consists in (or is defined as) the separation of elements, then it makes no sense to speak of the destruction of an element.
"One would, however, like to say: existence cannot be attributed to an element, for if it did not exist, one could not even name it and so one could say nothing at all of it."
It's hard to see the problem here, since it sounds perfectly sensible to say that if a particular element did not exist then we could not name it or talk about it. But this will become clearer with Wittgenstein's remarks on the standard metre which immediately follow, which he calls "an analogous case".
I won't rehash the standard metre discussion, except to re-quote Fogelin who interprets Wittgenstein here as saying that it makes no sense "to use something as a standard and simultaneously judge its accordance with that standard."
Wittgenstein then asks us to imagine a similar case to the standard metre in which a sample of "standard sepia" is kept hermetically sealed in Paris. W states that it will likewise "make no sense to say of this sample either that it is of this colour or that it is not".
Wittgenstein's reference to this being "an analogous case" makes clear that when he earlier said that existence cannot be attributed to an element, what he implied was that neither existence nor non-existence can be attributed to an element.
In the reference work 'Wittgenstein's Philosophical Investigations' edited by Dr Arif Ahmed, Dale Jacquette identifies a principle at work which connects the opening lines of §50 (regarding the existence of elements) with the standard metre and standard sepia examples. Mr Jacquette calls it the "polarity or complementarity principle" such that whenever "the predication or its negation or complement serve no purpose in a genuine language-game, the predication and its negation or complement are judged to have violated a rule of philosophical grammar". In the case of the standard metre, since it makes no sense to say that the standard metre is not one metre long, then it likewise makes no sense to say that it is one metre long.
Wittgenstein goes on to say that a standard or sample, such as the standard metre, "is not something that is represented, but is a means of representation". A 'means of representation' is a way of representing something. The standard metre is an example of this since it introduces, or prepares the way for, our use of the metre (as a length) in our language-games. However, once introduced, our use of the metre as a length is 'something that is represented'; something that is used within our language-games. The parallels of this distinction to the distinction drawn between names and descriptions at §49 are now apparent: preparation for use in the language-game vs. use in the language-game.
Hence: "And to say "If it did not exist, it could have no name" is to say as much and as little as: if this thing did not exist, we could not use it in our language-game.—What looks as if it had to exist, is part of the language. It is a paradigm in our language-game; something with which comparison is made. And this may be an important observation; but it is none the less an observation concerning our language-game—our method of representation."