At the beginning of his Philosophical Investigations (1945-49), Wittgenstein quotes a passage from the Confessions (398) of Saint Augustine:
When they (my elders) named some object, and accordingly moved towards something, I saw this and I grasped that the thing was called by the sound they uttered when they meant to point it out. Their intention was shown by their bodily movements, as it were the natural language of all peoples: the expression of the face, the play of the eyes, the movement of other parts of the body, and the tone of voice which expresses our state of mind in seeking, having, rejecting, or avoiding something. Thus, as I heard words repeatedly used in their proper places in various sentences, I gradually learnt to understand what objects they signified; and after I had trained my mouth to form these signs, I used them to express my own desires.This empiricist account is remarkably similar, in fact, to how Locke described the acquisition of language in his 1690 Essay on Human Understanding. It was an influential account; Wittgenstein, however, rejects it as simplistic: 'Augustine does not speak of there being any difference between kinds of word. . . Augustine, we might say, does describe a system of communication; only not everything that we call language is this system'. It is an account suited to a conception of language consisting of concrete nouns—'apple', 'chair', and so forth—but cannot deal with more sophisticated words—from 'if' and 'but' to 'exasperation' and 'piety'. For Wittgenstein, the acquisition of language comes not from 'explanation', but rather from 'training':
An important part of the training will consist in the teacher's pointing to the objects, directing the child's attention to them, and at the same time uttering a word; for instance, the word "slab" as he points to that shape. . . This ostensive teaching of words can be said to establish an association between the word and the thing. . . But if the ostensive teaching has this effect, —am I to say that it effects an understanding of the word? Don't you understand the call "Slab!" if you act upon it in such-and-such a way? —Doubtless the ostensive teaching helped to bring this about; but only together with a particular training. With different training the same ostensive teaching of these words would have effected a quite different understanding.The learning of words—the establishment of associations 'between the word and the thing'—can only operate in a pre-determined context, such that the learner understands what it is he is to learn. In this context, which Wittgenstein calls a 'language game', the child knows what it means when a teacher points to a slab and says, 'Slab'.
Isn't it ironic, then, that Wittgenstein's great predecessor in critiquing the notion of 'ostensive definition' was, in fact, Saint Augustine? The Bishop of Hippo had already written his dialogue De Magistro nine years prior to his Confessions; it was the first work he wrote after his conversion to the faith in 387, and still in the mould of his pre-Christian works, such as Contra Academicos. For my money, Augustine's early dialogues are the most sophisticated philosophical works since Aristotle—a stylistic return to Plato, after the dialogue form had been diluted by Cicero's bland moderateness.
De Magistro concerns the role of signs in the acquisition of language and knowledge. It begins with Augustine asking his disciple Adeodatus the question, 'When we speak, what does it seem to you we want to accomplish?' The reply is 'So far as it now strikes me, either to teach or to learn'. The rest of the work is given to countering this thesis. Of things, words can only give ostensive definitions:
When a question is raised about things that aren't signs, these things can be exhibited either by doing them after the query, if they can be done, or by giving signs with which they may be brought to one's attention.But Augustine is just as aware as Wittgenstein about the problems with this:
If anyone should ask me what it is to walk while I was resting or doing something else, and I should attempt to teach him what he asked about without a sign, by immediately walking, how shall I guard against his thinking that it's just the amount of walking I have done?In other words, ostensive definition can only teach when the learner knows how to interpret it correctly; he needs a context for the demonstration. We notice not only a similarity of reasoning, but also of style—Augustine, like Wittgenstein, constantly returns to concrete examples and thought-experiments to demonstrate his points. Here's another:
Suppose that someone unfamiliar with how to trick birds (which is done with reeds and birdlime) should run into a birdcatcher outfitted with his tools, not birdcatching but on his way to do so. On seeing this birdcatcher, he follows closely in his footsteps, and, as it happens, he reflects and asks himself in his astonishment what exactly the man's equipment means. Now the birdcatcher, wanting to show off after seeing the attention focused on him, prepares his reeds and with his birdcall and his hawk intercepts, subdues, and captures some little bird he has noticed nearby. I ask you: wouldn't he then teach the man watching him what he wanted to know by the things itself rather than by anything that signifies?The difference here is that the man watching already knows what birdcatching is. The demonstration only 'jogs his memory' of the craft as a whole. Signs cannot teach the knowledge of things: 'When a sign is given to me, it can teach me nothing if it finds me ignorant of the thing of which it is the sign; but if I'm not ignorant, what do I learn through the sign?' Signs can only remind us of things we already know, or teach us other signs:
Words have force only to the extent that they remind us to look for things; they don't display them for us to know. . . From words, then, we learn only words.Augustine is essentially a rationalist, like his master, Plato—the only source of knowledge is a spiritual faculty, a prior awareness, of which external evidence can only remind us:
Regarding each of the things we understand, however, we don't consult a speaker who makes sounds outside us, but the Truth that presides within over the mind itself, though perhaps words prompt us to consult Him.Plato brought in the doctrine of anamnesis—recollection of the world of Forms, experienced by the soul before mortal birth. Augustine instead invokes God; in his account, which is much more rigorous than Plato's Meno, he anticipates the objections made by Wittgenstein to the empiricist account of learning, although he draws from them very different conclusions. If Augustine retreats to an even more internalist epistemology—the criterion of truth being in one's spirit—the Austrian philosopher advocates almost pure externalism: language as a group activity, an acquired behaviour.
Update 28/09/07: Alasdair MacIntyre, in his 1984 essay 'The Relationship of Philosophy to its Past', writes: 'Augustine’s account of the place of ostensive definition in language learning points towards the divine illumination of the mind; Wittgenstein’s very similar account—that Wittgenstein erroneously took his account to be at odds with Augustine’s reinforces my central thesis—points towards the concept of a form of life.' So it's not just me.