Now think of the following use of language: I send someone shopping. I give him a slip of paper marked "five red apples". He takes the slip to the shopkeeper, who opens the drawer marked "apples"; then he looks up the word "red" in a chart and finds a colour sample next to it; then he says the series of elementary number-words - I assume that he knows them by heart - up to the word "five", and for each number-word he takes an apple of the same colour as the sample out of the drawer. -- It is in this and similar ways that one operates with words. -- "But how does he know where and how he is to look up the word 'red' and what he is to do with the word 'five'?" -- Well, I assume that he acts as I have described. Explanations come to an end somewhere. - But what is the meaning of the word "five"? - No such thing was in question here, only how the word "five" is used.
This passage, from §1 of the book, has always charmed me. The situation presented is a beguiling mix of the mundane and the strange – what could be more prosaic than buying apples? And yet no grocer’s store in the world has ever operated quite like this. Doubtless, this was intentional on Wittgenstein’s part; it helps us to see a simple use of language with fresh eyes. And for all its apparent whimsy, the scene’s “action” has clearly been chosen with great care: it quietly introduces a remarkable number of the book’s major themes.
First, it is an example of a “language-game” (although this term is not introduced until §7) – an intentionally basic situation designed to focus attention on language in use rather than any abstract account of its “essence”.
Then there are the specific words involved: five red apples. A number, a colour and a physical object. Together with the shopkeeper’s responses, they draw attention to the variety of uses words can have. In particular, they undermine the notion that the basic function of words is to name objects. Apples, of course, are objects, but what about “red” or “five”? In this situation it seems clear that no objects are involved (but compare it to, say, “Red is more vivid than brown” or “five is a prime number”).
The end of the passage then introduces two striking features of the Investigations: the impatient interjection of questions by an imagined interlocutor, and Wittgenstein’s adroit side-stepping of those questions. The interlocutor reappears throughout the book – in fact at times the Investigations resembles a loosely-structured dialogue. This is linked (I think) to Wittgenstein’s conception of his philosophy as a sort of therapy – a careful untangling of the linguistic knots which lead to philosophical bewilderment (for example, the notion that the essence of words is to name objects). And so the book often reads like a very strange session on a psychiatrist’s couch.
As for Wittgenstein’s response to the interlocutor’s questions, it is not so much that he doesn’t answer them (though he doesn’t) – it is more that he rejects their very validity. It is symptomatic of the depth of Wittgenstein’s attack on “traditional” philosophy (the philosophy of Descartes, Hume and his own earlier work) that he does not seek to provide solutions to its problems but to reject the basic assumptions upon which it is founded – misguided assumptions that, he believes, give rise to the problems in the first place.
Finally, we get the first example of a cryptic aphorism in the almost throw-away remark “Explanations come to an end somewhere”. This obliquely draws attention to the role of explanations in language. As Wittgenstein later points out (eg, §10), they are given to correct (or prevent) particular types of misunderstanding in particular contexts. So long as they do that job (in other words, so long as people act in the required way) no further explanation is necessary. They come to rest in behaviour, not in an “ultimate” or “foundational” explanation which somehow prevents any possible misunderstanding. And yet it is precisely such “ultimate” explanations that philosophy so often seeks to provide.