Environmental Ethics
and Public Policy
Ernest Partridge, Ph.D

HOME PAGE                             
    Philosophy and Religion
    Ethics, Moral Issues, the Law
    The Environment

On Politics
    The Crisis
    Foreign Relations, War, Peace
    The Media
    The Elections
    Civil Liberties and Dissent
    Republicans & the Right
    Democrats & the Left
    Lies, Propaganda & Corruption
    Culture War & Religious Right
    Coup d'Etat, 2000

Published Papers

Unpublished Papers

Reviews, Lectures, etc.    

Internet Publications


Lecture Topics

Conscience of a Progressive
    (A Book in Progress)

A Dim View of Libertarianism

Rawls and the Duty to Posterity
    (Doctoral Dissertation)

The Ecology Project

For Environmental Educators

The Russian Environment

    (Critiques of Post Modernism)

Notes from the Brink
    (Peace Studies)

The Gadfly's Bio Sketch

The Gadfly's Publications

The Online Gadfly: Editorial Policy

The Gadfly's E-Mail: gadfly@igc.org

Classical Guitar:
"The Other Profession






How to be Sure of Yourself by Not Saying Anything

Ernest Partridge


Seminar: Perception and Verification
Prof. T. M. Reed
University of Utah, April 16, 1968


"The pursuit of the incorrigible is one of the most venerable bugbears in the history of philosophy," writes J. L. Austin as he opens Section X of Sense and Sensibilia.(1964,) I quite agree, but not always for the same reasons as Austin. In this paper, I propose to supplement his criticism of the "bugbear" of incorrigibility as it appears in A. J. Ayer's book, The Foundations of Empirical Knowledge. (1964) More specifically, I will challenge Ayer's view that (a) there can be propositions based upon immediate sense date – i.e. a "language of sense-data"; and (b) that such propositions are capable of delivering "'incorrigible' foundations of empirical knowledge."

Austin should be credited for scoring some telling criticisms of Ayer's position (albeit, I find a few minor points of dispute with Austin). However, since space is limited, and since conflict is far more stimulating than concord, I will direct my major attention to Ayer.

Let us then roll out the target and look it over. To begin, I can scarcely improve upon Austin's summary of what I will call the ''Foundations of Knowledge Doctrine:"

In a nutshell, the doctrine is that knowledge, 'empirical' knowledge,.,. . has foundations. It is a structure of the upper tiers of which are reached by inferences, and the foundations are the data on which these inferences are based. (So of course as it appears--there just have to be sense-data). Now the trouble with inferences is that they may be mistaken; whenever we take a step, we may put a foot wrong. Thus – so the doctrine runs – the way to identify the upper tiers of the structure of knowledge is to ask whether one might be mistaken, whether there is something that one can doubt; if the answer is Yes, then one is not in the basement. And conversely, it will be characteristic of the data that in their case no doubt is possible, no mistake can be made. So to find the data, the foundations, look for the incorrigible. (105)

My principal complaint with this account is the suggestion that any and all "foundations theorists" are in fact stuck with "the incorrigible," when, as a matter of fact, many might get by with the idea that the "foundations" are just the "least corrigible." (E. g. Ouine, Popper). However, Ayer seems quite willing to be adorned with this albatross, and so we'll let Austin's account above stand pretty much as given.

Strange to say, Ayer does not appear to accommodate us with as concise and clear a statement of his own doctrine. The best that I can do is to present the best samples that I could find, and to attempt to extract therefrom, the nerve of the issue. I trust that the reader will forgive this laboring, for it is most important that the point at issue be explicated.

In our first excerpt, Ayer begins his recitation of the doctrine with a detached, impersonal tone. But notice how, at the close, he confesses his faith:

It is held to be characteristic of an 'incorrigible' proposition that it is completely verified by the existence of the sense datum which it describes; and so it is inferred that to doubt the truth of such a proposition is not merely irrational but meaningless; for it is only significant to doubt where there is a logical possibility of error. The argument is, in short, that if one uses a sentence such as "this is green" merely to designate a present sense-datum, then no proposition is being asserted to the truth of which any further evidence would be relevant. . . The propositions which such sentences were supposed to express might be said to be indubitable on the ground that it was not significant to say that one doubted them in any other but a purely verbal sense.

From this it may be concluded that all that is involved in the claim that there are indubitable or incorrigible empirical propositions is that people do sometimes use sentences in the way that the sentence "this is green" was used in my example, or at any rate that they could use certain sentences in this way, if they choose. And I do not see any reason to deny that this is so. (My italics. A. J. Ayer, Foundations of Empirical Knowledge, 83-4).

From this we might validly extract, at least, the following: "Sense data can on some occasions, provide the bases for incorrigible propositions." It will be the main task of this paper to invalidate the concept of an "incorrigible sense-datum proposition." Ayer reiterates his position in the following:

In the case of a sentence which refers to a sense-datum, it is possible to be mistaken about the truth of the proposition expressed, so long as one is not actually observing the relevant fact. But there is no such possibility of error when the sense-datum is actually being sensed. For in that case, the use of the sentence is prescribed by a rule of the language; so that to make an assertion that does not correspond to the fact is either to tell a deliberate lie or else to make a verbal mistake. (111)

We might then safely conclude that Ayer would accept the following: "When a sense-datum is actually being sensed, it is not possible to be mistaken about the truth of the proposition expressing this fact." This in turn clearly points to the central target of my analysis: the belief that sense-data can yield incorrigible propositions.


Throughout Ayer's book, we find (in one form or another) this crucial pronouncement:2 "In the domain of sense data, whatever appears, is real." (123) This might be interpreted to mean that of any present sense-datum X, "X is just what it seems to be." Now what in fact does this deny? Ayer takes great pains to show that this "usage" denies that (a) "more is given to us than we are actually aware of," or (b) that "only part of what we apprehend is really given." (117) Alternately stated this usage denies (a) that "sense-data can have properties that they do not appear to have" or (b) that some data "can appear to have properties that they do not really have." (117) Ayer dismisses these interpretations, so as "to make the distinction between sense-data and material things as sharp as possible." (117-118)

Now then, if we say "incorrigibly" of a present sense-datum X, "X is just what it seems to be," what in fact are we saying? What else is – or isn't – X? Well, it seems that we are immediately at a stop. To say anything else, would be to link it up with something not-given--and we can't do that without introducing contingent, corrigible assertions. We are, remember, seeking an incorrigible proposition.

But can't we make a statement involving "facts," yet contained within the field of awareness? Let's try it out with Ayer's own example: "This is Green."

Of course, we can't ask "What is it that is green?" if by that we wish to identify "this" with grass, or a tree, or whatever, for to do so is to introduce "material objects" and with them "corrigibility." So let's try asking "What do you mean 'this is green'?" What does "green" mean? "Well, like what I sensed when. . ." Now hold on! You can't leave the present, for we must not admit the possibility of error, and "the possibility of my being mistaken, in what is not merely a verbal sense, depends upon the fact that my judgment goes beyond the evidence upon which it is immediately based. It connects an experienced sense datum with other possible sense-data which are not simultaneously given, and in doing so it allows room for doubt and error." (82-83)

In other words, "green" in Ayer's "incorrigible" proposition "this is green," must be as bound to the present instant as the "this." We simply cannot bring in "green" like (some other) X" – not even "some other X-datum."

And so, having no links with other times and other sense-data (i.e. those not now present), "greenness" simply shrinks to equivalence with "this." We must omit reference, predication, qualification, inference, for all these must transcend the here-and-now. But without these, in what sense have we language or meaning? And if we have sense experience without meaning, what have we? What is left? W. M. Urban gives a provocative response to this:

. . .something would be left if language were gone. But the question is, just what would be left? Could we call it knowing? Awareness. . .would still be there – the mere whatness of sense datum and perhaps its otherness, although the latter is perhaps questionable. But what is it that the intellect, in Bergson's words, "will still affirm in implicit terms?" The only thing, I feel sure, would be something like "that is that." In order that anything else should be affirmed, language. . . would have to come back. . .

What would be left if language were gone? Nothing that is affirmed – even in "implicit terms." In other words, we 'have' something, the sensation, but we 'know' nothing. . .Knowledge does not arise until the intellect affirms, either explicitly or implicitly, and such affirmation is impossible without linguistic form. (342)

Be this as it may, will we still have "incorrigibility?" Of course! If "this is green" is to mean nothing more than "that is that," or simply "Behold!" period! – who can possibly deny it? No one can deny this simply because there is nothing to deny. We deny judgments, and surely this is no judgment – not unless, contra hypothesis, the predicate is allowed to expand beyond the immediate, and thus open itself to fallibility.

Well then, just what is the way out of this? Very easy. We simply do not allow that our perception must be "immaculate." We must acknowledge that there must be more to our data than immediately meet our senses. We must accept that "more is given to us than we are actually aware of." (117) In C. S. Peirce's terms, we must acknowledge that all "givens" are signs – with "hooks" of meaning, association and inference that reach beyond the immediacy of our here-and-now awarenesses. The immediate "this," if it is to be an element of a proposition – that is, be available to a meaningful language--must be spliced to a predicate that refers beyond the immediate. That is to say, the predicate must not be a simple repetition of the subject "this." A sentence, we must remember, is molecular--a hybrid. It must employ concepts derived from and comprehended in terms of other times and places. On the other hand, sense-data, to be "incorrigible," must be now--immediate. But if such "givens" are to be articulated in meaningful sentences, they must be related to classes (of things, relations, ,qualities) not immediate. And if so related, the data just might turn out not to be the sort of things they are predicated to be. Not necessarily merely because of "a verbal error," but because they simply might be found not to belong to the classes that they were said to belong to. You might be convinced that "this is a green patch." But what if you look out the window to find the grass and trees to be a radically different color--say, what you thought was "red?" Impossible? I'm quite inclined to agree. But inconceivable? Logically inconsistent? Hardly. Or try this: formulate any so-called "sense-datum statement" that would satisfy Ayer's "incorrigibility standards." Take care then to exclude all reference or presuppositions, in any term, "to sense data-which are not simultaneously given." (83) What then will you have? Not a sentence in any worthy senze. And if not a sentence--then no language. Thus the phrase "incorrigible sense-datum language" simply makes no sense!

In summary, then to the degree that sense data are "incorrigible," they are wholly unqualified to stand as "foundations of knowledge." The same quality of "immediacy" that renders sense data "incorrigible" forbids their connection with other sense data or class concepts to form judgments and inferences or other meaningful sentence forms. Conversely, to the degree that "sense data" are involved in meaningful (and non-tautologous) sentences, they relate to classes and conditions beyond their immediate manifestations, and are thus contingent and fallible.


Ayer's search among "sense data" for incorrigible foundations of knowledge fails simply because there are no such discrete "building blocks" underlying human knowledge. Nothing is "given" to human awareness that is not infused with meaning. There are no "bits" of untouched data to sort out and pile up, as one "builds" their experience and knowledge. Rather, as Cassirer puts it:

Man lives in a symbolic universe. Language, myth, art and religion are parts of this universe. They are the varied threads which weave the symbolic net, the tangled web of human experience. All human progress in thought and experience refines upon and strengthens this net. No longer can man confront reality immediately; he cannot see it, as it were, face to face. Physical reality seems to recede in proportion as man's symbolic activity advances. Instead of dealing with the things themselves man is in a sense constantly conversing with himself. (43)

Midas-like, man transforms what he encounters, both in terms of his past experience and his future anticipations – and as his past and future are codified in the "symbolic universe" that surrounds him as he "converses with himself."

The inalienable role of meaning to perception of sense-data might be readily demonstrated. Consider the following figures:

What do you make of them? Give up? The first is a portrait of a "vicious circle." The second depicts a soldier and his dog turning the corner of a building. Now I defy you to "see" these figures now, just as you did a moment before.3 Meaning, I submit, is virtually inseparable from "sense-data." Alter the meaning of the datum, and it's "appearance" changes. (Who, among your friends, "looks" the way he did when you first met him? Recall how now familiar places appeared when you first saw them, and how different they appear now.)

It would seem, then, that we never encounter discrete bits of sensed information, isolated for our phenomenological convenience, from past and future entanglements. Quite the contrary, our percepts are entangled in Cassirer's web of symbolism. We might also (and not inconsistently) conceive of our percepts in Peirce's terms, as interpretants of the past and hypotheses of the future. Thus interpreted, we see that our percepts by themselves, are inherently incomplete and have meaning and significance only as they are integrated into the process of living.4

If this be so, the "Foundations of Knowledge" doctrine is woefully misguided and quite inadequate to the task of revealing the source and nature of empirical knowledge.



The following comments just didn't seem to fit smoothly into the body of my paper, but they might be of some use in provoking discussion. This is a list of five other fundamental difficulties raised by critics of the "foundations of knowledge doctrine":5

a) Just how are material object statements derived from sense data statements without employing material object stigmas to do so. (E.g.. "There is a table in the next room?" "This floor is supported by beams?").6

b) How can a set of hypothetical statements (which, it is alleged by some critics, sense data statements must be) add up to categorical statements about material objects. [Hirst]

c) How can knowledge that is intrinsically private be translated into knowledge of public objects?

d) Isn't "private language" in fact derived from the public language?

e) Even more, isn’t such a thing as a "private language" impossible and incomprehensible. (Wittgenstein and Malcolm are the most noteworthy advocates of this view).

If, upon examination, we find that these challenges (and mine) are substantial, we might then wonder "how did anyone ever come to believe in 'incorrigible sense data statements’ in the first place?" It would seem that many were drawn astray by the dread of an "infinite regress." Hard-core "basic statements" or "basic meanings" were taken as a panacea against this trap.

Quinton summarizes the argument:

The traditional form of the doctrine of foundations holds that there must be some intuitive belief it any beliefs are to be justified at all. By an intuitive belief is meant one which does not owe its truth or credibility to some other belief or beliefs from which it can be inferred. For a belief to be justified it is not enough for it to be accepted, let alone merely entertained. There must also be good reasons for accepting it. Certainly some beliefs are justifiable by reference to others, but only if these other beliefs are themselves established or well confirmed. If every belief was dependent on others for its justification, no belief would be justified at all, for in this case to justify any belief would require the justification of an infinite series of beliefs. So if any belief is to be justified, there must be a class a basic, non-inferential beliefs to bring the regress of justification to a halt. [58]




1.    This marvelous pun is not, alas, my own, I've forgotten just who is responsible for it.

2.    Or better, "linguistic convention"--as Ayer is so anxious that we not forget.

3.    While at Northland College (1993-7) I showed my classes a satellite photo of Lake Superior. I then noted that many see a wolf’s head in this image. (See for yourself, dear reader). Every student "saw" this immediately. I then challenged them to perceive the image of the lake as they did, a few seconds earlier, before they were told of the wolf’s head. Impossible! (2009)

4.    I expand upon this aspect of Peirce’s philosophy in Section III of my seminar paper, "Metaphysician, Heal Thyself! – A Dim View of Peirce’s Realism," Autumn, 1976.

5.    Most of these are reviewed by Anthony Quinton in its paper. "The Foundations of Knowledge" reprinted in British Analytic Philosophy, Williams and Montefiore, Eds.

6.    These points are carefully argued by R. J. Hirst in his book. The Problems of Perception, (Allen & Unwin), Chapters 2 & 3.



Austin, J. L., Sense & Sensibilia, New York, Oxford University Press, 1964.

Ayer, A.J., The Foundations of Empirical Knowledge, London, MacMillan, 1964.

Cassirer, Ernst, An Essay on Man, New York, Anchor, 1954.

Hirst, R. J., The Problems of Perception, Allen and Unwin,.

Quinton, "The Foundations of Knowledge, British Analytical Philosophy, Williams and Montefiore, eds.

Urban, W.M., Language and Reality, New York


Dr. Ernest Partridge is a consultant, writer and lecturer in the field of Environmental Ethics and Public Policy. He has taught Philosophy at the University of California, and in Utah, Colorado and Wisconsin. He publishes the website, "The Online Gadfly" (www.igc.org/gadfly) and co-edits the progressive website, "The Crisis Papers" (www.crisispapers.org).  Dr. Partridge can be contacted at: gadfly@igc.org .