Verifiability Criterion of Meaning
Before considering the actual truth or falsity of statements asserting how one ought to achieve the good life, logical positivists insist that we first test statements for meaningfulness. That is, we should apply the verifiability criterion of meaning to any claim purported to say something about the world: A statement is meaningful if and only if we can state which sensory observations would determine whether the statement is true or false.
Consider the following statements: “This is a room,” “There is a hippopotamus in this room,” “The temperature at the center of the sun is 64 million degrees centigrade,” “God exists,” and “Murder is wrong.” Applying the verifiability criterion, a logical positivist concludes that the first three statements are meaningful and that the final two are meaningless. In the first three cases, we can state what sensory observations would determine truth of falsity—for example, we can state what we would see, hear, and touch if there is a hippopotamus in the room. (Logical positivists only ask whether the probable truth or falsity is determinable through sensory observations; in addition, they concern themselves with testability-in-principle in applying the verifiability criterion—not worrying, for example, whether anyone can actually measure the temperature at the center of the sun.) However, “God exists” is a different sort of statement. If we think of God as a supernatural being, that is, a being beyond the natural world, then no sensory observation involving sight, sound, touch, taste, or smell can establish truth or falsity. Therefore the statement is meaningless.
The statement, “Murder is wrong,” is also meaningless, although it requires more detailed analysis. For example, in trying to establish meaningfulness, suppose I cite statistical (factual) evidence showing the likelihood that persons committing murders will be apprehended by law enforcement authorities. While logical positivists admit here the presence of factual evidence, based upon sensory observation, they deny that this evidence establishes the wrongness of murder since no factual evidence exists that being apprehended is wrong. If I present further factual evidence establishing the likelihood of conviction through the criminal justice system following apprehension, then the positivist demands factual evidence that being convicted is wrong. Suppose I then present factual evidence establishing the likelihood of execution or a long prison-term following conviction. The positivist can respond by demanding factual evidence that being executed or given a long prison-term is wrong. Even if I now point out that, factually, execution entails death and a long prison-term entails loss of freedom, the positivist can demand factual evidence showing that death is wrong or that loss of freedom is wrong. Ultimately, according to logical positivists, we must grant that no factual evidence, that is, no evidence gained through sensory observation, can establish the truth or falsity of the statement, “Murder is wrong.” Hence the statement is meaningless.
Clearly, logical positivists recognize one kind of knowledge, namely, the facts of science established through sensory observations. (They also recognize logic and mathematics as a kind of knowledge, even granting that statements in these fields can attain the status of certainties, although they conclude that such statements say nothing about the world of sensory experience.) However, if a statement does not belong to logic or mathematics and is not capable of verification through sensory observation, then it cannot ever have any status as knowledge. Of course, persons can have quite strong emotions with respect to such statements; but they should not associate these emotions with knowledge. Ayer states the case this way:
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, add 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.1
According to Ayer's position, from the standpoint of knowledge, no significant difference exists between your saying that murder is wrong and saying that you hate chocolate ice cream or screaming at basketball games. In such cases, only feelings or emotions are being expressed; there can be no ethical knowledge. This position is often referred to as the emotive theory of ethics, since ethical judgments are regarded merely as expressions of emotion or feeling. Consequently, the question, “How can the good life be known?,” is unanswerable.
Although there can be no knowledge that murder is wrong, we make a serious mistake if we conclude that logical positivists approve of murder. The statement, “Murder is right,” is just as meaningless as its contrary. Furthermore, positivists admit that our feelings about the wrongness of murder may be very important to us, although they make no knowledge claim about the wrongness of murder in such an admission.
Logical Positivism and Society
We may well wonder whether any society can function for any period of time based upon acceptance of this emotive theory of ethics. Positivists have several ways of dealing with such a challenge.
First, so long as most people in a society share the same moral feelings—for example, most people feel that murder is wrong—a stable social structure is possible.
Secondly, even if there are differences in moral feelings, the possibility always exists that we can persuade others to take on our own feelings, quite apart from any genuine knowledge about right or wrong.
Finally, positivists argue that many supposedly “ethical” disputes are really disguised factual disputes. For example, the acceptability of capital punishment seems to be a continuing source of ethical dispute. Suppose however that two parties to the dispute base their judgment of acceptance or rejection upon whether or not capital punishment deters crime. That is, one party supports capital punishment on the grounds that it deters crime whereas the other party opposes it on the ground that it does not. In such a case, the dispute is factual, not ethical, since we can settle it by gathering factual evidence about the effectiveness or ineffectiveness of capital punishment in deterring crime within a society. So, for example, we can check homicide rates when capital punishment was or was not in effect. Because so many ethical disputes resemble the example given here, logical positivism does not really do away with discussion of many issues that most people regard as being ethical in nature. Hence the positivists' rejection of ethics is not as catastrophic as it first seems.
Controversies: Some Objections and Possible Replies
(Note About Objections and Possible Replies: You should look upon the objections and possible replies as opportunities for further thought rather than as definitive statements. Holders of the original position are not likely to be overwhelmed by the objections; and critics of the original position are not likely to be convinced by the possible replies. These objections and possible replies accomplish a proper goal if they push you to think more deeply about an issue, leading you to seek more clarity and justification in drawing your own conclusions.)
(1) Materialism and Verifiability Criterion
There is no sound reason why anyone should accept the verifiability criterion of meaning as a presupposition for the establishment of meaningfulness. Far from being a neutral standard, the criterion is a materialistic principle specifically designed to reduce all knowledge, except that in logic and mathematics, to description of physical reality. The apparent “meaninglessness” of ethical statements is really just the result of an excessively materialistic point of view that is never adequately justified by the logical positivists.
A Possible Reply: The verifiability criterion is a rule about the way language is to be used and therefore requires no justification. Correctness in the use of language follows from a set of rules that establish what we mean by correctness in that language. But we cannot expect evidence to establish the correctness of the initial rules themselves.
(2) Values and Human Nature
By basing values upon human nature, we can establish the truth of ethical statements. For example, if human beings are so constituted by nature that they seek pleasure, then the pursuit of pleasure is good and the statement, “Human beings ought to seek pleasure,” is true.
A Possible Reply: The fact that human beings desire pleasure cannot establish that pleasure is good. To make this leap commits the naturalistic fallacy.2 Facts about our desires are different in kind from judgments of what we ought to do; and we cannot derive the one from the other.
(3) The Practical Irrelevance of Logical Positivism
In reducing what most people regard as ethical disputes to factual ones, logical positivists do not challenge the meaningfulness of what most people take to be the subject matter of ethics. And since most people are concerned with issues rather than terminology, very little ethics is lost by the positivistic critique.
A Possible Reply: This objection is not really a challenge to logical positivism, since it does not refute anything maintained by positivists. It only justifies the sloppy use of language. Unfortunately, when we use language sloppily, we frequently lead ourselves into error and, what is often worse, into useless disputes that sap effort and never reach resolution. The history of ethics provides a graphic display of such useless disputes.
4.3 . What would be the results if the verifiability criterion of meaning were applied to the following statements:
No one has ever seen an amoeba with the naked eye,
Most people agree that murder is an unacceptable activity,
Human beings have an immortal soul?
4.31 Do you agree with the analysis given for the statement, “Murder is wrong,” from a positivist's point of view? Would you agree with the emotive theory of ethics?
4.32 Consider the three ways logical positivists meet the charge that a society cannot function for any period of time based upon the emotive theory of ethics. How adequate is their response to the charge?
4.33 Evaluate the various objections to logical positivism mentioned in the text. Be sure to consider how a logical positivist may reply to each objection. Which is the strongest objection? The weakest? Would you offer other objections beside those mentioned in the text? If so, what are they? What is your general evaluation of logical positivism?
1. Alfred Jules Ayer, Language, Truth, and Logic (New York: Dover Books, 1952), p. 107.
2. Strictly speaking, the term naturalistic fallacy refers to a specific position taken by the British philosopher G.E.Moore. See the reference to it in the Possible Reply to Objection (2) in the section on Intuition. In more general usage, however, any attempt to derive value statements from fact statements commit the naturalistic fallacy. We should note though that not all philosophers agree that a genuine fallacy occurs.
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