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The final extract in our survey of accounts of knowledge in the Western philosophical tradition takes us back to the problem of the foundations of knowledge, a problem that had figured prominently in the thought of René Descartes in the seventeenth century (see extract 4, above). In a highly influential paper the American philosopher Wilfrid Sellars takes as his target the idea that all our knowledge must be derived or inferred from certain basic authoritative statements, knowledge of which is ‘non-inferential’ – that is, these statements are not themselves inferred from any other statements. As paradigms of such supposedly authoritative statements Sellars instances, on the one hand, basic analytic statements such as ‘two plus two makes four’, and, on the other hand, simple reports of immediate sensory experience, for example ‘this is red’. (This follows a long tradition concerning the two fundamental types of proposition on which all our knowledge is supposed to be based; compare for example David Hume, Part II, extract 7, below).

Knowledge, on the model Sellars is about to attack, is like a complex edifice whose whole weight rests ultimately on its foundations. In the case of empirical knowledge, what supposedly makes the foundations secure is that, at the level of basic sensory experience, I am confronted with a datum (e.g. an impression of redness) that directly validates my speech-act when I declare ‘this is red’. As Sellars puts it, ‘one is committed to a stratum of authoritative nonverbal episodes (“awareness”) the authority of which accrues to a superstructure of verbal actions, provided that the expressions occurring in these actions are properly used. These self-authenticating episodes would constitute the tortoise on which stands the elephant on which rests the edifice of empirical knowledge …’ .

It looks deceptively simple: when I see the red apple, there is an experiential datum – a ‘given’, and it is this that confers authority on my statement ‘this is red’.¹ But Sellars acutely argues that under scrutiny this idea – the ‘myth of the given’ as he calls it – turns out to be highly problematic. For the correctness of my judgement about this apple’s being red depends on a whole network of complex linguistic rules about the standard conditions for the appropriate use of the predicate ‘red’ (roughly, something counts as red only if it would be called ‘red’ by a normal English-speaking observer in normal light). So the picture of what is ‘given’ somehow validating my knowledge in isolation must be wrong. It is, Sellars argues, ‘a matter of simple logic, that one couldn’t have observational knowledge of any fact unless one knew many other things as well’.

Sellars’s work is part of a reaction against the atomistic models of knowledge found for example in Hume (in the eighteenth century) and in the logical positivists (earlier in the twentieth),² in favour of a more ‘holistic’ or systematic conception (compare Hegel, extract 9 above). It also follows the lead of Wittgenstein in rejecting first-personal accounts of the basis of knowledge, and acknowledging instead its fundamentally social or inter-personal nature.³ But if the ‘myth of the given’ is abandoned, are we not left with knowledge as a mere network of interlinked statements, each depending on some other statement, without any direct ‘point of contact’ with an actual mind-independent reality? One might fear this would leave us with the picture referred to at the close of the extract, of ‘a great Hegelian serpent of knowledge with its tail in its mouth (Where does it begin?).’ Sellars ends by suggesting, plausibly, that neither of these two models is satisfactory (the ‘myth of the given’, on the one hand, and the ‘serpent’ of mere systematic coherence on the other); but exactly how to construct a more adequate model for the human epistemic enterprise is still a matter of fierce philosophical debate.

One of the forms taken by the Myth of the Given is the idea that there is, indeed must be, a structure of particular matter of fact such that (a) each fact can not only be noninferentially known to be the case, but presupposes no other knowledge either of particular matter of fact, or of general truths; and (b) such that the noninferential knowledge of facts belonging to this structure constitutes the ultimate court of appeals for all factual claims – particular and general – about the world. It is important to note that I characterized the knowledge of fact belonging to this stratum as not only noninferential, but as presupposing no knowledge of other matter of fact, whether particular or general. It might be thought that this is a redundancy, that knowledge (not belief or conviction, but knowledge) which logically presupposes knowledge of other facts must be inferential. This, however, as I hope to show, is itself an episode in the Myth.

Now, the idea of such a privileged stratum of fact is a familiar one, though not without its difficulties. Knowledge pertaining to this level is noninferential, yet it is, after all, knowledge. It is ultimate, yet it has authority. The attempt to make a consistent picture of these two requirements has traditionally taken the following form:

Statements pertaining to this level, in order to ‘express knowledge’ must not only be made, but, so to speak, must be worthy of being made, credible, that is, in the sense of worthy of credence. Furthermore, and this is a crucial point, they must be made in a way which involves this credibility. For where there is no connection between the making of a statement and its authority, the assertion may express conviction, but it can scarcely be said to express knowledge.

The authority – the credibility – of statements pertaining to this level cannot exhaustively consist in the fact that they are supported by other statements, for in that case all knowledge pertaining to this level would have to be inferential, which not only contradicts the hypothesis, but flies in the face of good sense. The conclusion seems inevitable that if some statements pertaining to this level are to express noninferential knowledge, they must have a credibility which is not a matter of being supported by other statements. Now there does seem to be a class of statements which fill at least part of this bill, namely such statements as would be said to report observations, thus, ‘This is red.’ These statements, candidly made, have authority. Yet they are not expressions of inference. How, then, is this authority to be understood?

Clearly, the argument continues, it springs from the fact that they are made in just the circumstances in which they are made, as is indicated by the fact that they characteristically, though not necessarily or without exception, involve those so-called token-reflexive expressions which, in addition to the tenses of verbs, serve to connect the circumstances in which a statement is made with its sense …

It would appear, then, that there are two ways in which a sentence token can have credibility: (1) The authority may accrue to it, so to speak, from above, that is, as being a token [or instance] of a sentence type all the tokens of which, in a certain use, have credibility, e.g. ‘2 + 2 = 4.’ In this case, let us say that token credibility is inherited from type authority. (2) The credibility may accrue to it from the fact that it came to exist in a certain way in a certain set of circumstances, e.g. ‘This is red.’ Here token credibility is not derived from type credibility.

Now the credibility of some sentence types appears to be intrinsic – at least in the limited sense that it is not derived from other sentences, type or token. This is, or seems to be, the case with certain sentences used to make analytic statements. The credibility of some sentence types accrues to them by virtue of their logical relations to other sentence types, thus by virtue of the fact that they are logical consequences of more basic sentences. It would seem obvious, however, that the credibility of empirical sentence types cannot be traced without remainder to the credibility of other sentence types. And since no empirical sentence type appears to have intrinsic credibility, this means that credibility must accrue to some empirical sentence types by virtue of their logical relations to certain sentence tokens, and, indeed, to sentence tokens the authority of which is not derived, in its turn, from the authority of sentence types.

The picture we get is that of their being two ultimate modes of credibility: (1) The intrinsic credibility of analytic sentences, which accrues to tokens as being tokens of such a type; (2) the credibility of such tokens as ‘express observations’, a credibility which flows from tokens to types.

Let us explore this picture, which is common to all traditional empiricisms, a bit further. How is the authority of such sentence tokens as ‘express observational knowledge’ to be understood? It has been tempting to suppose that in spite of the obvious differences which exist between ‘observation reports’ and ‘analytic statements’, there is an essential similarity between the ways in which they come by their authority. Thus, it has been claimed, not without plausibility, that whereas ordinary empirical statements can be correctly made without being true, observation reports resemble analytic statements in that being correctly made is a sufficient as well as necessary condition of their truth. And it has been inferred from this – somewhat hastily, I believe – that ‘correctly making’ the report ‘This is green’ is a matter of ‘following the rules for the use of “this”, “is” and “green”’. Three comments are immediately necessary:

(1) First a brief remark about the term ‘report’. In ordinary usage a report is a report made by someone to someone. To make a report is to do something. In the literature of epistemology, however, the word ‘report’ or ‘Konstatierung’⁴ has acquired a technical use in which a sentence token can play a reporting role (a) without being an overt verbal performance, and (b) without having the character of being ‘by someone to someone’ – even oneself. There is, of course, such a thing as ‘talking to oneself’… but, as I shall be emphasizing in the closing stages of my argument, it is important not to suppose that all ‘covert’ verbal episodes are of this kind.

(2) My second comment is that while we shall not assume that because ‘reports’ in the ordinary sense are actions, ‘reports’ in the sense of Konstatierungen are also actions, the line of thought we are considering treats them as such. In other words, it interprets the correctness of Konstatierungen as analogous to the rightness of actions. Let me emphasize, however, that not all ought is ought to do, nor all correctness the correctness of actions.

(3) My third comment is that if the expression ‘following a rule’ is taken seriously, and is not weakened beyond all recognition into the bare notion of exhibiting a uniformity – in which case the lightning–thunder sequence would ‘follow a rule’ – then it is the knowledge or belief that the circumstances are of a certain kind, and not the mere fact that they are of this kind, which contributes to bringing about the action.

In the light of these remarks it is clear that if observation reports are construed as actions, if their correctness is interpreted as the correctness of an action, and if the authority of an observation report is construed as the fact that making it is ‘following a rule’ in the proper sense of this phrase, then we are face to face with givenness in its most straightforward form. For these stipulations commit one to the idea that the authority of Konstatierungen rests on nonverbal episodes of awareness – awareness that something is the case, e.g. that this is green – which nonverbal episodes have an intrinsic authority (they are, so to speak, ‘self-authenticating’) which the verbal performances (the Konstatierungen) properly performed ‘express’. One is committed to a stratum of authoritative nonverbal episodes (‘awareness’) the authority of which accrues to a superstructure of verbal actions, provided that the expressions occurring in these actions are properly used. These self-authenticating episodes would constitute the tortoise on which stands the elephant on which rests the edifice of empirical knowledge …

But what is the alternative? We might begin by trying something like the following: An overt or covert token of ‘This is green’ in the presence of a green item is a Konstatierung and expresses observational knowledge if and only if it is a manifestation of a tendency to produce overt or covert tokens of ‘This is green’ – given a certain set – if and only if a green object is being looked at in standard conditions. Clearly on this interpretation the occurrence of such tokens of ‘This is green’ would be ‘following a rule’ only in the sense that they are instances of a uniformity, a uniformity differing from the lightning–thunder case in that it is an acquired causal characteristic of the language user. Clearly the above suggestion … won’t do as it stands. Let us see, however, if it can’t be revised to fit the criteria I have been using for ‘expressing observational knowledge’…

[We] have seen that to be the expression of knowledge, a report must not only have authority, this authority must in some sense be recognized by the person whose report it is. And this is a steep hurdle indeed. For if the authority of the report ‘This is green’ lies in the fact that the existence of green items appropriately related to the perceiver can be inferred from the occurrence of such reports, it follows that only a person who is able to draw this inference, and therefore who has not only the concept green, but also the concept of uttering ‘This is green’ – indeed, the concept of certain conditions of perception, those which would correctly be called ‘standard conditions’ – could be in a position to token ‘This is green’ in recognition of its authority. In other words, for a Konstatierung ‘This is green’ to ‘express observational knowledge’, not only must it be a symptom or sign of the presence of a green object in standard conditions, but the perceiver must know that tokens of ‘This is green’ are symptoms of the presence of green objects in conditions which are standard for visual perception.

Now it might be thought that there is something obviously absurd in the idea that before a token uttered by, say, Jones could be the expression of observational knowledge, Jones would have to know that overt verbal episodes of this kind are reliable indicators of the existence, suitably related to the speaker, of green objects. I do not think that it is. Indeed, I think that something very like it is true. The point I wish to make now, however, is that if it is true, then it follows, as a matter of simple logic, that one couldn’t have observational knowledge of any fact unless one knew many other things as well. And let me emphasize that the point is not taken care of by distinguishing between knowing how and knowing that, and admitting that observational knowledge requires a lot of ‘know how’. For the point is specifically that observational knowledge of any particular fact, e.g. that this is green, presupposes that one knows general facts of the form X is a reliable symptom of Y. And to admit this requires an abandonment of the traditional empiricist idea that observational knowledge ‘stands on its own feet’. Indeed, the suggestion would be anathema to traditional empiricists for the obvious reason that by making observational knowledge presuppose knowledge of general facts of the form X is a reliable symptom of Y, it runs counter to the idea that we come to know general facts of this form only after we have come to know by observation a number of particular facts which support the hypothesis that X is a symptom of Y.

And it might be thought that there is an obvious regress in the view we are examining. Does it not tell us that observational knowledge at time t presupposes knowledge of the form X is a reliable symptom of Y, which presupposes prior observational knowledge, which presupposes other knowledge of the form X is a reliable symptom of Y, which presupposes still other, and prior, observational knowledge, and so on? This charge, however, rests on too simple, indeed a radically mistaken, conception of what one is saying of Jones when one says that he knows that p. It is not just that the objection supposes that knowing is an episode; for clearly there are episodes which we can correctly characterize as knowings, in particular, observings. The essential point is that in characterizing an episode or a state as that of knowing, we are not giving an empirical description of that episode or state; we are placing it in the logical space of reasons, of justifying and being able to justify what one says.

Thus all that the view I am defending requires is that no tokening by S now of ‘This is green’ is to count as ‘expressing observational knowledge’ unless it is also correct to say of S that he now knows the appropriate fact of the form X is a reliable symptom of Y, namely that (and again I oversimplify) utterances of ‘This is green’ are reliable indicators of the presence of green objects in standard conditions of perception. And while the correctness of this statement about Jones requires that Jones could now cite prior particular facts as evidence for the idea that these utterances are reliable indicators, it requires only that it is correct to say that Jones now knows, thus remembers, that these particular facts did obtain. It does not require that it be correct to say that at the time these facts did obtain he then knew them to obtain. And the regress disappears …

The idea that observation ‘strictly and properly so-called’ is constituted by certain self-authenticating nonverbal episodes, the authority of which is transmitted to verbal and quasi-verbal performances when these performances are made ‘in conformity with the semantical rules of the language’, is, of course, the heart of the Myth of the Given. For the given, in epistemological tradition, is what is taken by these self- authenticating episodes. These ‘takings’ are, so to speak, the unmoved movers of empirical knowledge, the ‘knowings in presence’ which are presupposed by all other knowledge, both the knowledge of general truths and the knowledge ‘in absence’ of other particular matters of fact. Such is the framework in which traditional empiricism makes its characteristic claim that the perceptually given is the foundation of empirical knowledge.

If I reject the framework of traditional empiricism, it is not because I want to say that empirical knowledge has no foundation. For to put it this way is to suggest that it is really ‘empirical knowledge so-called’, and to put it in a box with rumours and hoaxes. There is clearly some point to the picture of human knowledge as resting on a level of propositions – observation reports – which do not rest on other propositions in the same way as other propositions rest on them. On the other hand, I do wish to insist that the metaphor of ‘foundation’ is misleading in that it keeps us from seeing that if there is a logical dimension in which other empirical propositions rest on observation reports, there is another logical dimension in which the latter rest on the former.

Above all, the picture is misleading because of its static character. One seems forced to choose between the picture of an elephant which rests on a tortoise (What supports the tortoise?) and the picture of a great Hegelian serpent of knowledge with its tail in its mouth (Where does it begin?). Neither will do. For empirical knowledge, like its sophisticated extension, science, is rational, not because it has a foundation but because it is a self-correcting enterprise which can put any claim in jeopardy, though not all at once.