“143. Let us now examine the following kind of language-game: when A gives an order B has to write down series of signs according to a certain formation rule. The first of these series is meant to be that of the natural numbers in decimal notation.—How does he get to understand this notation?— First of all series of numbers will be written down for him and he will be required to copy them. (Do not balk at the expression "series of numbers"; it is not being used wrongly here.) And here already there is a normal and an abnormal learner's reaction.—At first perhaps we guide his hand in writing out the series 0 to 9; but then the possibility of getting him to understand will depend on his going on to write it down independently.—And here we can imagine, e.g., that he does copy the figures independently, but not in the right order: he writes sometimes one sometimes another at random. And then communication stops at that point.—Or again, he makes 'mistakes" in the order.—The difference between this and the first case will of course be one of frequency.—Or he makes a systematic mistake; for example, he copies every other number, or he copies the series 0, 1, 2, 3, 4, 5, .... like this: 1, 0, 3, 2, 5, 4, . . . . . Here we shall almost be tempted to say that he has understood wrong. Notice, however, that there is no sharp distinction between a random mistake and a systematic one. That is, between what you are inclined to call "random" and what "systematic". Perhaps it is possible to wean him from the systematic mistake (as from a bad habit). Or perhaps one accepts his way of copying and tries to teach him ours as an offshoot, a variant of his.—And here too our pupil's capacity to learn may come to an end.” Though it is not said by W, what is important here is the essential role of showing in understanding the sense of ‘what is said’. W is ‘pointing out’ that, where a person is being instructed in a “series of numbers”, that person may conceivably make what we regard as ‘mistakes’, and their ‘mistakes’ may even have a systematic character so that we are “tempted to say that he has understood wrong”. While W does not here say it, it is implicit that a person could not make such mistakes if the sense of the “series” was said in ‘what is said’ here. Of course, we could try to explain their mistakes as arising because they do not understand the sense of ‘what is said’ here [to instruct them in the “series”]:- but if the sense is said in ‘what is said’ how can they not understand it? How can they understand ‘what is said’ at all [which they may do, as their response may show some understanding that ‘what is said’ concerns what we understand as a mathematical series], and yet still be mistaken as to the sense of ‘what is said’ – if that sense is said in ‘what is said’? The implicit answer is that, for W, they can have some understanding of ‘what is said’, yet also fail to understand its sense as we do, because the sense of ‘what is said’ is not said in ‘what is said’. Also ‘what is said’ may be understood in more than one sense, so a person may understand the sense of ‘what is said’ correctly in certain respects but not in others. The ‘key tenet’ holds that the sense of ‘what is said’ can only be shown. So when they make ‘mistakes’ in writing out the series, so that it is clear they do not understand the sense of the series, we try to teach them by showing them various things [not simply repeating ‘what is said’ as if this conveys its own sense] – we try to show them the sense so that they may understand it: and we can imagine various ways we might try to show them. If they write ‘1,0,2,3,4,5’ etc. we might begin by repeating the correct order ‘0,1,2,3,4,5,’; but if this does not show them the correct sense of the “series”, we might try to show them by shaking our head at their series and then writing out other ‘wrong series’ [e.g. ‘0,2,1,3,5,4’, ‘0,5,2,4,3,1’ etc.] and shaking our head so as to show them ‘what is a wrong series’; and then perhaps writing the correct series and nodding so as to show them ‘what is the correct series’. Or we might link the writing of each number in the correct series with a number of objects we consecutively place in a box: so after ‘0’ we point to an empty box, after ‘1’ we place one object in the box (and point to show the link between the number in the series and the number of objects in the box), and after ‘2’ we place another object in the box (and point to show the link) etc. Or, if what this seeks to show is not understood, we begin with the empty box then move to the number ‘0’ in the series, then put one object in the box and move to the number ‘1’ in the series etc. And so on. We might exhaust all the ways we can think to show them the sense of the “series”. But if all these ways fail to convey to them ‘what is a wrong series’ from ‘what is the correct series’ – if what can only be shown here is not understood – there is nothing to be said so that they may understand what they do not understand by what is shown (unless, of course, something is ‘said’ that inspires understanding because the pupil understands _‘what is shown’_ by ‘what is said’). If ‘showing’ fails to convey the sense of ‘what is said’, there is no further recourse to ‘what is said’ for explanation of its sense, for ‘what is said’ does not say its own sense (185: “Or suppose he pointed to the series and said: "But I went on in the same way." — It would now be no use to say: "But can't you see . . . . ?" — and repeat the old examples and explanations.”). As grasping the sense depends on the pupil grasping what can only be shown, if we exhaust our ways of showing them the sense and still they do not understand then, in this way, “our pupil's capacity to learn may come to an end.”Why? Because we have nothing left to show them and there is nothing to be said that can convey the sense by ‘saying’ the sense. In the next numbered section, W remarks on the role of showing here, and to show that what he is doing is also showing [not saying]: “144. What do I mean when I say "the pupil's capacity to learn may come to an end here"? Do I say this from my own experience? Of course not. (Even if I have had such experience.) Then what am I doing with that proposition? Well, I should like you to say: "Yes, it's true, you can imagine that too, that might happen too!"—But was I trying to draw someone's attention to the fact that he is capable of imagining that?——I wanted to put that picture before him, and his acceptance of the picture consists in his now being inclined to regard a given case differently: that is, to compare it with this rather than that set of pictures. I have changed his way of looking at things. (Indian mathematicians: "Look at this.")” How can W change our way of looking at things [or, as W asks, what is W doing with the proposition “"the pupil's capacity to learn may come to an end here"?”]? By showing how ‘what can only be shown’ plays a fundamental role in understanding sense and “the capacity to learn” sense. This role is often invisible to us because we often do understand ‘what can only be shown’ unproblematically – perhaps without any need to conspicuously show it. But it does not matter that in our normal experience the pupil understands the series ‘0,1,2,3’ etc. without our having to try to conspicuously show the sense of ‘what is said’ when we state such a series. The point is that if we ‘imagine’ how we would teach a pupil who did not understand, we see the inescapable and fundamental role of ‘what can only be shown’ in conveying and explaining sense. We see that the sense of ‘what is said’ is not said in ‘what is said’. W’s view, that the sense of ‘what is said’ is not said in ‘what is said’, was previously illustrated by W pointing out that ‘what is said’ is always compatible with more than one sense. At 152 W ‘shows’ that a formula does not say its own sense because a person could be aware there is such a formula – a ‘what is said’ – without understanding its sense:- 152. But are the processes which I have described here understanding! "B understands the principle of the series" surely doesn't mean simply: the formula "an = . . . . " occurs to B. For it is perfectly imaginable that the formula should occur to him and that he should nevertheless not understand. "He understands" must have more in it than: the formula occurs to him. And equally, more than any of those more or less characteristic accompaniments or manifestations of understanding. As is illustrated before and subsequent to this:- this “more in it” than ‘what is said’ reflects the ‘key tenet’, and is a “more in it” than can only be shown not said. “S185. Let us return to our example (143). Now—judged by the usual criteria—the pupil has mastered the series of natural numbers. Next we teach him to write down other series of cardinal numbers and get him to the point of writing down series of the form o, n, 2n, 3n, etc. at an order of the form "+n"; so at the order "+1" he writes down the series of natural numbers. — Let us suppose we have done exercises and given him tests up to 1000. Now we get the pupil to continue a series (say +2) beyond 1000 — and he writes 1000, 1004, 1008, 1012. We say to him: "Look what you've done!" — He doesn't understand. We say: "You were meant to add two: look how you began the series!" — He answers: "Yes, isn't it right? I thought that was how I was meant to do it." —— Or suppose he pointed to the series and said: "But I went on in the same way." — It would now be no use to say: "But can't you see . . . . ?" — and repeat the old examples and explanations. — In such a case we might say, perhaps: It comes natural to this person to understand our order with our explanations as we should understand the order: "Add 2 up to 1000, 4 up to 2000, 6 up to 3000 and so on." Such a case would present similarities with one in which a person naturally reacted to the gesture of pointing with the hand by looking in the direction of the line from finger-tip to wrist, not from wrist to finger-tip.” This last remark is like a philosophical joke but the point is serious: if attempts to show the sense of ‘what is said’ are to succeed, the person being taught must understand ‘what we seek to show’ in the same sense as we understand ‘what we seek to show’. Failure to convey a given sense by ‘showing’ could occur if they can make no sense of ‘what we seek to show’. But failure can also occur if they take ‘what we seek to show’ and make sense of it but different to the sense we take it to convey. Then ‘what is shown’ by us, as we understand it, will not teach them the sense we want to convey. But implicit here is the ‘key tenet’ that the sense of ‘what is said’ is not said in ‘what is said’ but can only be shown. For when a person applies a formula ‘wrongly’ – ‘wrongly’ according to our understanding – there is nothing said in the formula that we can point to in order to correct them – we can only try to show they have not understood the sense of the formula correctly, perhaps by showing them the correct sense. contd. at III C