LOGICAL POSITIVISM

 

From Essential Selections in 19th and 20th Century Philosophy, by James Fieser

Home: www.utm.edu/staff/jfieser/class

Copyright 2014, updated 5/1/2015

 

RUDOLPH CARNAP: THE ELIMINATION OF METAPHYSICS (“The Elimination of Metaphysics through the Analysis of Language,” 1932)

 

Meaningful Statements vs. Pseudo Statements

From the Greek skeptics to the empiricists of the 19th century there have been many opponents of metaphysics. The nature of the concerns raised have been very different. Some declared that the doctrine of metaphysics is false because it contradicts empirical knowledge. Others say it is uncertain because it goes beyond the limits of human knowledge. Many anti-metaphysicians declared that preoccupation with metaphysical questions is unfruitful. In any case, whether these can now be answered or not, it is unnecessary to tend to them in view of the very practical task to which working people dedicate themselves each day!

            With the development of modern logic, it has become possible to give a new and sharper response to the question of the validity and justification of metaphysics. There are positive and negative results to the investigations of "applied logic" or "epistemology" which, through logical analysis, clarifies the cognitive content of scientific statements and thus the meaning of the words occurring in sentences. The positive result is developed in the field of empirical science; the individual terms of the various branches of science are clarified; their formal-logical and epistemological context is exhibited. The negative result is in the field of metaphysics (including all philosophy of value and ethical theory) where logical analysis shows that the alleged statements in this area are completely pointless.

            Thus a radical elimination of metaphysics is reached, which had not yet been possible from the earlier anti-metaphysical standpoints. We find related ideas in some earlier considerations, for example, those of the nominalistic sort. But the decisive implementation is only now possible after the development of logic in recent decades, which has become a tool of sufficient sharpness.

            When we say that the so-called sentences of metaphysics are meaningless, we mean this word in the strictest sense. In lose sense it is customary sometimes to refer to a sentence or a question as meaningless if their use is completely unfruitful (for example, the question: "How big is the average body weight of persons in Vienna, whose telephone numbers end with 3?"); or a sentence that is patently false (for example, "in 1910, Vienna had 6 inhabitants"), or such, which is not only empirically, but logically wrong, and contradictory (for example, "of the persons A and B, each is year older than the other ").

            Such sentences, while unfruitful or wrong, are nevertheless meaningful; for, only meaningful sentences can ever divide (theoretically) between the fruitful and unfruitful, the true and false. By contrast, a series of words is meaningless in the strict sense when it forms no sentence within a certain predefined language. It may happen that such a sequence of words at first glance looks as if it were a sentence; in this case we call it a pseudo-statement. Our thesis now claims that the alleged sentences of metaphysics are revealed as pseudo-propositions by logical analysis.

            A language consists of vocabulary and syntax, that is, it comes from a collection of words that have a meaning, and from rules of sentence formation; these rules specify how sentences can be formed from words of various kinds. Accordingly, there are two types of pseudo-statements:  either they contain words that is mistakenly thought to have meaning, or, while occurring words indeed have meanings, they are constructed in a syntactically irregular manner, so that they do not make sense.

            We will see examples that pseudo-statements of both kinds occur in metaphysics. Later we will need to consider the reasons for our claim that the entirety of metaphysics consists of such pseudo-statements.

 

2. The Significance of a Word

If a word (in a given language) has meaning, it is customary to say that it also describes a "concept ". If it just looks as if the word has meaning when in fact it does not, we speak of it as a "pseudo-concept". . . .

            The result of our considerations may be briefly summarized. Let us call "a" any word and "S (a)" the elementary proposition in which it occurs. The necessary and sufficient condition for "a" to have meaning can be specified in any of the following formulations that say basically the same thing:

 

1. The empirical criteria for "a" are known.

2. It is clear from what protocol sentences "S (a)" can be derived.

3. The truth conditions for "S (a)" are fixed.

4. The verification method of "S (a)" is known.

 

3 Metaphysical Words without Meaning

With many words of metaphysics it can be shown that they do not meet the previously specified condition, and so they are without meaning. Take the example of the metaphysical term "principle" (and as principle of being, not as a principle of knowledge or principle). Various metaphysicians answer the question of what is the (highest) "principle of the world" (or of "things", of "existence", "of being"), as, for example, that it is water, number, form, the movement, life, spirit, idea, the unconscious, action, the good, and the like.  In this metaphysical question, to find the meaning given to the word "principle", we must ask the metaphysician for the conditions under which a sentence of the form "x is the principle of y is" true and under which it is false. In other words, we ask for the criteria of application or the definition of the word "principle".

            The metaphysician replies something like this: "x is the principle of y "is to say that "y it follows from x", "the existence of y is based on the existence of x", "y is given by x" or the like. But these words are ambiguous and vague. They often do have a clear meaning; for example, we say of a thing or process y that it "arises" from x, if we observe that from things or events like x there often or always follows things like y (causal relationship in the sense of lawful succession). But the metaphysician tells us that he does not mean this empirically ascertainable relationship; otherwise the metaphysician’s theses would be the simple empirical principles as those of physics.

            The word "arises" here should not be construed as a relation of temporal and causal sequence, which the word usually means; yet no other criterion of its meaning will be offered. Consequently, in contrast to the word’s empirical meaning, there is the alleged "metaphysical" meaning of the word, which is none at all. . . . The word has therefore been stripped of its former meaning, without getting a new meaning, and all that remains is a word as an empty shell. It is still connected through association to mental conception of the word from earlier times; they connect with new conceptions and feelings within the context in which we now use the word. But a meaning the word has not thereby been retained; and it is also more meaningless, since we cannot specify a path for verification.

            Another example is the word “God” . . . . Just like the examples of "principle" and "God" that we have considered, most of the specifically metaphysical terms are also without meaning, such as "idea," "the Absolute", "the unconditioned", "infinity", "the Being of beings" "non-being", "thing in itself", "absolute spirit," "objective spirit", "essence", "being-in-itself", "being-in-and-for-itself", "emanation" "," manifestation ","articulation", "ego ","non-ego" etc. With these expressions, it is no different than with the word invented "babig" in the earlier example devised. The metaphysician tells us that the empirical truth-conditions cannot be specified; when he adds that the word still has some “meaning” for him, we thus know that he is only alluding to accompanying conceptions and feelings, but which give the word no meaning. The alleged metaphysical sentences containing such words have no meaning, they say nothing, and are mere pseudo-propositions. As to an account of how they historically developed, we will explain later. . . .

 

6. Meaninglessness of all Metaphysics

The above examples of metaphysical sentences that we have analyzed were all taken from a treatise [by Heidegger]. But the results are similar, sometimes literally the same, with other metaphysical systems. When that Treatise [by Heidegger] quotes with approval a sentence of Hegel’s (that "pure being and pure nothing are therefore the same"), this appeal is done quite rightly. For, the metaphysics of Hegel has the exact same logical character as we have found that modern metaphysics [by Heidegger]. And the same is true for the other metaphysical systems, although the manner of expressions and thus the type of logical error is a little different from the type of the examples discussed. . . . The judgment of meaninglessness also ultimately applies to those metaphysical systems which are usually inaccurately described as “epistemological”, namely, realism (if they say they want more than the empirical fact that a sequence of events have a specific regularity, which makes possible the application of inductive method)  and its opponents, namely,  subjective idealism , solipsism, phenomenalism, positivism (in the earlier sense).

            But what in general remains for philosophy if all sentences that say something are empirical in nature and belong to factual science? What remains are not propositions, or theories, or systems, but only one method, namely, logical analysis. In the above, we have shown the application of this method in its negative use: it was used here for the eradication of meaningless words, meaningless pseudo-statements. In its positive use, it serves to clarify the meaningful words and phrases, and provide the logical foundation of factual science and mathematics. The negative application of the method is necessary and important in the present period. However, in the present period the positive application is more useful. We cannot further discuss this here, but it is the implied task of logical analysis and foundational inquiry that is meant by “scientific philosophy” in contrast with metaphysics.

 

7 Metaphysics as an Expression about Life

When we say that the propositions of metaphysics are completely meaningless and say nothing, even for someone who intellectually agrees with our conclusion this will still cause an uncomfortable sense of unsettlement. How could so many men of various ages and nations, including the strongest minds, devote so much trouble and genuine passion to metaphysics when it is nothing but mere words meaningless strung together? And how are we to understand why books on the subject have had such a powerful effect on readers up to the present day, while at the same time they contain absolutely nothing, not errors? These concerns are justified insofar as metaphysics actually does contains something; even though there is no theoretical content. The (pseudo) propositions of metaphysics do not represent facts, neither of existing ones (then they would be true statements) nor non-existing ones (then they would be at least be false propositions); they serve to express feelings about life.

            Perhaps we may assume that metaphysics developed from mythology. The child is angry with the "bad table” that hurt him; the Primitive person tries to appease the threatening demon of the earthquake, or he worships the deity of the fertile rain in gratitude. Here we have personifications of natural phenomena before us, which are the quasi-poetic expression of the emotional relationship between man and environment. The legacy of mythology is, on the one hand passed down to poetry, which consciously intensifies the power of myth in life. On the other hand, it is passed on to theology which turns myth into a system. What then is the historical role of metaphysics? Perhaps we may see it as the replacement for theology at the systematic level of conceptual thinking. The (alleged) supernatural sources of knowledge of theology are replaced with natural, but (supposedly) trans-empirical sources of knowledge. . . .

            For the purpose of our discussion here, art is an adequate means of expressing the feeling of life, but metaphysics is inadequate. Naturally, there is nothing wrong in and of itself with using any arbitrary expression. With metaphysics, however, the situation is such that, through the form of its works, it misrepresents itself as something it is not. This form is that of a system of statements that are in (apparently) logically related to each other in the form of a theory. This theoretical content is simulated, while, however, as we have seen, there is no content available. Not only the reader, but also the metaphysician himself is deluded that something is being said by his metaphysical propositions, and that facts are described. The metaphysician believes he travels in a place where there is truth and falsehood. In reality, however, he says nothing, but just expresses something like an artist. . . .

 

OGDEN AND RICHARDS: EMOTIVISM (The Meaning of Meaning, 1923)

 

Emotive and Symbolic uses of Words are Distinct though usually Overlap (Ch. 7)

In ordinary everyday speech each phrase has not one but a number of functions. We shall in our final chapter classify these under five headings; but here a twofold division is more convenient, the division between the symbolic use of words and the emotive use. The symbolic use of words is statement; the recording, the support, the organization and the communication of references. The emotive use of words is a more simple matter, it is the use of words to express or excite feel­ings and attitudes. It is probably more primitive. If we, say “The height of the Eiffel Tower is 900 feet” we are making a statement, we are using symbols in order to record or communicate a reference, and our symbol is true or false in a strict sense and is theoretically verifiable. But if we say “Hurrah!” or “Poetry is a spirit” or “Man is a worm,” we may not be making statements, not even false statements; we are most probably using words merely to evoke certain attitudes.

            Each of these contrasted functions has, it will be seen, two sides, that of the speaker and that of the listener. Under the symbolic function are included both the symbolization of reference and its communica­tion to the listener, i.e., the causing in the listener of a similar reference. Under the emotive function are included both the expression of emotions, attitudes, moods, intentions, etc., in the speaker, and their com­munication, i.e., their evocation in the listener. As there is no convenient verb to cover both expression and evocation, we shall in what follows often use the term’ evoke’ to cover both sides of the emotive function, there being no risk of misunderstanding. In many cases, moreover, emotive language is used by the speaker not because he already has an emotion which he desires to express, but solely because he is seeking a word which will evoke an emotion which he desires to have; nor, of course, is it necessary for the speaker himself to experience the emotion which he attempts to evoke.

            It is true that some element of reference probably enters, for all civilized adults at least, into almost all use of words, and it is always possible to import a reference, if it be only a reference to things in general. The two functions under consideration usually occur together but none the less they are in principle distinct. So far as words are used emotively no question as to their truth in the strict sense can directly arise. In­directly, no doubt, truth in this strict sense is often involved. Very much poetry consist of statements, symbolic arrangements capable of truth or falsity, which are used not for the sake of their truth or falsity but for the sake of the attitudes which their acceptance will evoke. For this purpose it fortunately happens, or rather it is part of the poet’s business to make it happen, that the truth or falsity matters not at all to the acceptance. Provided that the attitude or feeling is evoked the most important function of such language is fulfilled, and any symbolic function that the words may have is instrumental only and subsidiary to the evocative function.

 

Scientific Truth as the Criterion of Distinction between Symbolic and Emotive

This subtle interweaving of the two functions is the main reason why recognition of their difference is not universal. The best test of whether our use of words is essentially symbolic or emotive is the question “Is this true or false in the ordinary strict scientific sense?” If this question is relevant then the use is symbolic, if it is clearly irrelevant then we have an emotive utterance.

            But in applying this test we must beware of two dangers. There is a certain type of mind which although it uses evocative language itself cannot on reflection admit such a thing, and will regard the question [of scientific truth] as relevant upon all occasions. For a larger body of readers than is generally supposed poetry is unreadable for this reason. The other danger is more important. Corresponding in some degree to the strict sense of true and false for symbolic statements (True-S), there are senses which apply to emotive utterances (True-E). Critics often use True-E of works of art, where alternative symbols would be ‘convincing’ in some cases, ‘sincere’ in others, ‘beautiful’ in others, and so on. And this is commonly done without any awareness that True-E and True-S are different symbols. Further there is a purely evocative use of True -- its use to excite attitudes of acceptance or admiration; and a purely evocative use of False -- to excite attitudes of distrust or disapprobation. When so used these words, since they are evocative, cannot, except by accident, be replaced by others; a fact which explains the common reluctance to relinquish their employment even when the inconvenience of having symbols so alike superficially as True-S and True-E in use together is fully recognized. In general that affection for a word even when it is admitted to be ambiguous, which is such a common feature of discussion; is very often due to its emotive efficiency rather than to any real difficulty in finding alternative symbols which will support the same reference. It is, however, not always the sole reason, as we shall see when we come in our final chapter to consider the condition of word­-dependence. . . .

 

Symbolic and Emotive uses often Disguise as the Other

But a more general consciousness of the nature of the two functions is necessary if they are to be kept from interfering with one another; and especially all the verbal disguises, by which each at times endeavors to pass itself off as the other, need to be exposed. It ought to be impossible to pretend that any scientific statement can give a more inspiring or a more profound ‘vision of reality’ than another. It can be more general or more useful, and that is all. On the other hand it ought to be impossible to talk about poetry or religion as though they were capable of giving knowledge, especially since ‘knowledge’ as a term has been so overworked from both sides that it is no longer of much service. A poem—or a religion, though religions have so definitely exploited the con­fusion of function which we are now considering, and are so dependent upon it, as to be unmistakably patho­logical growths—has no concern with limited and directed reference. It tells us, or should tell us, nothing. It has a different, though an equally important and a far more vital function—to use an evocative term in connection with an evocative matter. What it does, or should do, is to induce a fitting attitude to experi­ence. But such words as ‘fitting,’ ‘suitable’ or ‘appropriate’ are chilly, having little or no evocative power. Therefore those who care most for poetry and who best understand its central and crucial value, tend to resent such language as unworthy of its subject. From the evocative standpoint they are justified. But once the proper separation of these functions is made it will be plain that the purpose for which such terms are used, namely to give a strictly symbolic description of the function of poetry, for many reasons the supreme form of emotive language, cannot conflict with the poetic or evocative appraisal of poetry, with which poets as poets are concerned.

 

Ethical use of “Good” is Emotive, not Symbolic (Ch. 6)

It is often, indeed, impossible to decide, whether a particular use of symbols is primarily symbolic or emotive. This is especially the case with certain kinds of metaphor. When the Psalmist cries of his enemies, “They have sharpened their tongues like a serpent; adders’ poison is under their lips,” it is hard to determine whether an elusive similarity between the reptile and the persons he is describing is enabling him metaphorically to state something about them, or whether the sole function of his utterance is not to express his abhorrence of them and to promote similar attitudes towards them in his hearers. Most terms of abuse and endearment raise this problem, which, as a rule, it is, fortunately, not important to settle. The distinction which is important is that between utterances in which the symbolic function is subordinate to the emotive act and those of which the reverse is true. In the first case, however precise and however elaborate the references communicated may be, they can be seen to be present in an essentially instrumental capacity, as means to emotive effects. In the second case, how­ever strong the emotive effects, these can be seen to be by-products not essentially involved in the speech transaction. The peculiarity of scientific statement, that recent new development of linguistic activity, is its restriction to the symbolic function.

            If this restriction is to be maintained, and if scientific methods of statement are to be extended to fields such as those traditionally tended by philosophers, certain very subtle dangers must be provided for. Amongst these is the occurrence, in hitherto quite unsuspected numbers, of words which have been erroneously regarded without question as symbolic in function [but are really only emotive]. The word ‘good’ may be taken as an example. It seems probable that this word is essentially a collection of homonyms, such that the set of things, roughly, those in connection with which we heard it pronounced in early years (a good bed, a good kick, a good baby, a good God) have no common characteristic. But another use of the word is often asserted to occur, of which some at least of those which we have cited are supposed to be degenerations, where ‘good’ is alleged to stand for a unique, unanalysable concept. This concept, it is said, is the subject-matter of Ethics (cf. G.E. Moore, Principia Ethica, Chap. 1). This peculiar ethical use of ‘good’ is, we suggest, a purely emotive use. When so used the word stands for nothing whatever, and has no symbolic function. Thus, when we so use it in the sentence, ‘This is good,’ we merely refer to this, and the addition of ‘is good’ makes no difference whatever to our reference. When on the other hand, we say ‘This is red,’ the addition of ‘is red’ to ‘this’ does symbolize an extension of our reference, namely, to some other red thing. But ‘is good’ has no comparable symbolic function; it serves only as an emotive sign expressing our attitude to this, and perhaps evoking similar attitudes in other persons, or inciting them to actions of one kind or another.

            Of course, if we define ‘the good’ as ‘that of which we approve of approving,’ or give any such definition when we say “This is good,” we shall be making an assertion. It is only the indefinable ‘good’ which we suggest to be a purely emotive sign. The ‘something more’ or ‘something else’ which, it is alleged, is not covered by any definition of ‘good’ is the emotional aura of the word. …

 

AYER: THE VERIFICATION PRINCIPLE (from Language, Truth and Logic, 1936)

 

The Verification Principle briefly Explained (1946, Appendix)

. . . The principle of verification is supposed to furnish a criterion by which it can be determined whether or not a sentence is literally meaningful. A simple way to formulate it would be to say that a sentence had literal meaning if and only if the proposition it expressed was cither analytic or empirically verifiable.

 

Verification Principle and the Meaninglessness of Metaphysics (Preface)

The views which are put forward in this treatise derive from the doctrines of Bertrand Russell and Wittgenstein, which are themselves the logical outcome of the empiricism of Berkeley and David Hume. Like Hume, I divide all genuine propositions into two classes: those which, in his terminology, concern "relations of ideas", and those which concern “matters of fact”. The former class comprises the a priori propositions of logic and pure mathematics, and these I allow to be necessary and certain only because they are analytic. That is, I maintain that the reason why these propositions cannot be confuted in experience is that they do not make any assertion about the empirical world, but simply record our determination to use symbols in a certain fashion. Propositions concerning empirical matters of fact, on the other hand, I hold to be hypotheses, which can be probable but never certain. And in giving an account of the method of their validation I claim also to have explained the nature of truth.

            To test whether a sentence expresses a genuine empirical hypothesis, I adopt what may be called a modified verification principle. For I require of an empirical hypothesis, not indeed that it should be conclusively verifiable [i.e., the strong sense of verifiability], but that some possible sense-experience should be relevant to the determination of its truth or falsehood [i.e., the weak sense of verifiability]. If a putative proposition fails to satisfy this principle, and is not a tautology, then I hold that it is metaphysical, and that, being metaphysical, it is neither true nor false but literally senseless. It will be found that much of what ordinarily passes for philosophy is metaphysical according to this criterion, and. In particular, that it cannot be significantly asserted that there is a non-empirical world of values, or that men have immortal souls, or that there is a transcendent God.

 

Ethical Statements: Meaningless and Cannot be Contradictory (Ch, 6)

We begin by admitting that the fundamental ethical concepts are unanalysable, inasmuch as there is no criterion by which one can test the validity of the judgements in which they occur. So far we are in agreement with the absolutists [who hold that statements of value are not controlled by observation, but by a mysterious intellectual intuition]. But, unlike the absolutists, we are able to give an explanation of this fact about ethical concepts. We say that the reason why they are unanalysable is that they are mere pseudo-concepts. The presence of an ethical symbol in a proposition adds nothing to its factual content. Thus if I say to someone, “You acted wrongly in stealing that money,” I am not stating anything more than if I had simply said, “You stole that money.” In adding that this action is wrong I am not making any further statement about it. I am simply evincing my moral disapproval of it. It is as if I had said, “You stole that money,” in a peculiar tone of horror, or written it with the addition of some special exclamation marks. The tone, or the exclamation marks, adds nothing to the literal meaning of the sentence. It merely serves to show that the expression of it is attended by certain feelings in the speaker.

            If now I generalize my previous statement and say, “Stealing money is wrong,” I produce a sentence which has no factual meaning -- that is, expresses no proposition which can be either true or false. It is as if I had written “Stealing money!!” -- where the shape and thickness of the exclamation marks show, by a suitable convention, that a special sort of moral disapproval is the feeling which is being expressed. It is clear that there is nothing said here which can be true or false. Another man may disagree with me about the wrongness of stealing, in the sense that he may not have the same feelings about stealing as I have, and he may quarrel with me on account of my moral sentiments. But he cannot, strictly speaking, contradict me. For in saying that a certain type of action is right or wrong, I am not making any factual statement, not even a statement about my own state of mind. I am merely expressing certain moral sentiments. And the man who is ostensibly contradicting me is merely expressing his moral sentiments. So that there is plainly no sense in asking which of us is in the right. For neither of us is asserting a genuine proposition. . . .

 

SCHLICK: LOGICAL POSITIVISM REQUIRES LOGICAL POSSIBILITY, NOT EMPIRICAL POSSIBILITY (“Meaning and Verification” 1936)

 

Empirical Verifiability not Relevant to Meaning

Verifiability means possibility of verification. . . . For our purpose it suffices to distinguish between two of the many ways in which the word 'possibility' is used. We shall call them 'empirical possibility' and 'logical possibility'. . . . I propose to call 'empirically possible' anything that does not contradict the laws of nature. This is, I think, the largest sense in which we may speak of empirical possibility; we do not restrict the term to happenings which are not only in accordance with the laws of nature but also with the actual state of the universe (where 'actual' might refer to the present moment of our own lives, or to the condition of human beings on this planet, and so forth). If we chose the latter definition . . . we should not get the sharp boundaries we need for our present purpose. So 'empirical possibility' is to mean 'compatibility with natural laws'. . . .

            Is the possibility of verification which we insist upon of this empirical sort? In that case there would be different degrees of verifiability, the question of meaning would be a matter of more or less, not a matter of yes or no. In many disputes concerning our issue it is the empirical possibility of verification which is discussed. . . . Many of those who refuse to accept our criterion of meaning seem to imagine that the procedure of its application in a special case is somewhat like this: A proposition is presented to us ready made, and in order to discover its meaning we have to try various methods of verifying or falsifying it, and if one of these methods works we have found the meaning of the proposition; but if not, we say it has no meaning. If we really had to proceed in this way, it is clear that the determination of meaning would be entirely a matter of experience, and that in many cases no sharp and ultimate decision could be obtained. How could we ever know that we had tried long enough, if none of our methods were successful? Might not future efforts disclose a meaning which we were unable to find before?

            This whole conception is, of course, entirely erroneous. It speaks of meaning as if it were a kind of entity inherent in a sentence and hidden in it like a nut in its shell, so that the philosopher would have to crack the shell or sentence in order to reveal the nut or meaning. . . . 

            In other words, the possibility of verification which is relevant to meaning cannot be of the empirical sort; it cannot be established post festum [i.e., “after the feast”]. You have to be sure of it before you can consider the empirical circumstances and investigate whether or no or under what conditions they will permit of verification. The empirical circumstances are all-important when you want to know if a proposition is true (which is the concern of the scientist), but they can have no influence on the meaning of the proposition (which is the concern of the philosopher). . . . It must be emphasized that when we speak of verifiability we mean logical possibility of verification, and nothing but this.

 

Only Logical Possibility Relevant to Meaning

I call a fact or a process 'logically possible' if it can be described, i.e., if the sentence which is supposed to describe it obeys the rules of grammar we have stipulated for our language. (I am expressing myself rather incorrectly. A fact which could not be described would, of course, not be any fact at all; any fact is logically possible. But I think my meaning will be understood.) Take some examples. The sentences, 'My friend died the day after tomorrow'; 'The lady wore a dark red dress which was bright green'; 'The campanile is 100 feet and 150 feet high'; 'The child was naked, but wore a long white nightgown', obviously violate the rules which, in ordinary English, govern the use of the words occurring in the sentences. They do not describe any facts at all; they are meaningless, because they represent logical impossibilities.

            An opponent of our view might find a dangerous paradox or even a contradiction in the preceding explanations, because on the one hand we insisted so strongly on what has been called the "empirical-meaning requirement", and on the other hand we assert most emphatically that meaning and verifiability do not depend on any empirical conditions whatever, but are determined by purely logical possibilities. The opponent will object: if meaning is a matter of experience, how can it be a matter of definition and logic?

            In reality there is no contradiction or difficulty. The word 'experience' is ambiguous. Firstly, it may be a name for any so-called 'immediate data'—which is a comparatively modern use of the word—and secondly we can use it in the sense in which we speak e.g., of an 'experienced traveller', meaning a man who has not only seen a great deal but also knows how to profit from it for his actions. It is in this second sense (by the way, the sense the word has in Hume's and Kant's philosophy) that verifiability must be declared to be independent of experience. The possibility of verification does not rest on any 'experiential truth', on a law of nature or any other true general proposition, but is determined solely by our definitions, by the rules which have been fixed for our language, or which we can fix arbitrarily at any moment. All of these rules ultimately point to ostensive definitions, as we have explained, and through them verifiability is linked to experience in the first sense of the word. No rule of expression pre- supposes any law or regularity in the world (which is the condition of 'experience' as Hume and Kant use the word), but it does presuppose data and situations, to which names can be attached. The rules of language are rules of the application of language; so there must be something to which it can be applied. Expressibility and verifiability are one and the same thing. There is no antagonism between logic and experience. Not only can the logician be an empiricist at the same time; he must be one if he wants to understand what he himself is doing.

 

Example: The Reality of the Other Side of the Moon

Let us glance at some examples in order to illustrate the consequences of our attitude in regard to certain issues of traditional philosophy. Take the famous case of the reality of the other side of the moon (which is also one of Professor Lewis's examples). None of us, I think, would be willing to accept a view according to which it would be nonsense to speak of the averted face of our satellite. Can there be the slightest doubt that, according to our explanations, the conditions of meaning are amply satisfied in this case?

            I think there can be no doubt. For the question, 'What is the other side of the moon like?', could be answered, for instance, by a description of what would be seen or touched by a person located somewhere behind the moon. The question whether it be physically possible for a human being—or indeed any other living being—to travel around the moon does not even have to be raised here; it is entirely irrelevant. Even if it could be shown that a journey to another celestial body were absolutely incompatible with the known laws of nature, a proposition about the other side of the moon would still be meaningful. Since our sentence speaks of certain places in space as being filled with matter (for that is what the words 'side of the moon' stand for), it will have meaning if we indicate under what circumstances a proposition of the form, 'this place is filled with matter', shall be called true or false. The concept 'physical substance at a certain place' is defined by our language in physics and geometry. Geometry itself is the grammar of our propositions about 'spatial' relations, and it is not very difficult to see how assertions about physical properties and spatial relations are connected with 'sense-data' by ostensive definitions.

 

Source: Rudolph Carnap, “The Elimination of Metaphysics through the Analysis of Language,” (1932), tr. Alan Smithee; Charles K. Ogden and Ivor A. Richards, The Meaning of Meaning (1923), 6, 7; Alfred Jules Ayer, Language, Truth and Logic (1926), Preface, 6, Appendix; Moritz Schlick, “Meaning and Verification” (1936).

 

Questions for Review

1. Explain the following concepts in Carnap: meaninglessness, pseudo-statement, positive and negative aspects of modern logic.

2. What is Carnap’s critique of the metaphysical claims that "x is the principle of y" and “y arises from x”?

3. Explain the following concepts in Ogden: emotive vs. symbolic uses of words, the criterion of distinction between the two, and the necessary and sufficient conditions for a word to have meaning in a sentence.

4. Explain Ogden’s position on the emotive use of the word “good”.

5. Explain the following concepts in Ayer: verification principle, strong verification, weak verification, and why ethical statements cannot contradicted each other.

6. Explain what Schlick means by “empirical possibility” and “logical possibility”, and give some of his examples of logically impossible statements.

 

Questions for Analysis

1. Carnap, Ayer and Schick each have slightly different versions of the verification principle. Discuss how each of them would determine the meaningfulness of the statement “The universe and its contents double in size every minute.”

2. In 1922 Ogden did the first English translation of Wittgenstein’s Tractatus, and a year later Ogden’s theory of emotivism in The Meaning of Meaning (1923). It’s reasonable to suppose that the Tractatus influenced him. Compare and contrast Wittgenstein’s view of the inexpressibility of ethics with Odgen’s view of emotive and ethics, and discuss which, if either of them, is right.

3. Schlick argues that that verification is really about logical possibility, not empirical possibility. Evan Fales, in his book Causation and Universals (1990), writes that "the examples Schlick uses all involve something stronger than mere logical possibility. They are all cases in which the 'definition' is controlled by what relevant observations are physically possible -- that is, are such that making them would (presumably) not violate any causal laws." Explain Fales' point and discuss whether this compromises Schlick's position that verification is really about logical possibility.

4. A common criticism of logical positivism is that it is self-refuting: its verification principle is itself neither a tautology nor empirically verifiable; thus it fails its own criteria and is meaningless. A reply to this criticism is attributed to Carnap: the verification principle is only a recommendation, and not a strictly meaningful statement. This is implied by what Carnap called the Principle of Tolerance: “It is not our business to set up prohibitions, but to arrive at conventions. . . . In logic there are no morals. Everyone is at liberty to build up his own logic, i.e., his own form of language, as he wishes. All that is required of him is that, if he wishes to discuss it, he must state his methods clearly, and give syntactical rules instead of philosophical arguments.” (Carnap, Logical Syntax of Language, 1934, Sect. 17). Evaluate Carnap’s response to the self-refutation charge.

5. Another criticism of logical positivism is the paradox of verifiability, as summarized in the following argument. (a) The verification principle states that all non-tautological meaningful statements have empirically verifiable consequences. (b) The verification principle is either verifiable or it is not. (c) If it is verifiable, then both it and its contradiction are meaningful; consequently, it is meaningful to say that “some statement is meaningful yet has no empirically verifiable consequences”; and this means that the verification principle is false. (d) If it is not verifiable, then this means there is at least one unverifiable statement that is meaningful, which again means that the verification principle is false. (e) Therefore, on either supposition, the verification principle is false. Explain this criticism and discuss how a logical positivist might respond.

6. Another criticism of logical positivism is that it eliminates important scientific concepts that do not pass the verification test, such as theoretical entities like atoms and the Mendelian gene. Develop this criticism and discuss how a logical positivist respond to this criticism.

7. Logical positivism and pragmatism are similar in that they each tie the meaning of a statement to empirical experience. James states that conceptionshave indeed no meaning and no reality if they have no use” (Pragmatism, 8). However, James’s notion of tender-minded pragmatism allows for the meaningfulness of metaphysical, ethical, and religious statements that the logical positivist would find meaningless. Compare James’s tender-minded approach to Carnap’s or Ayer’s verification principle and discuss whether there is a way to make the verification principle a little more tender-minded.