A few months ago a caller on Catholic Answers Live said he didn’t believe that God exists because the belief cannot be proven true (verified) or false (falsified) based on empirical observation. What he meant was that there is nothing in our sense experience that can show whether the proposition “God exists” is true or false.
This objection arises out of the twentieth-century philosophical movement known as logical positivism. The British philosopher A.J. Ayer (1910-1989) was one of its main advocates.
In his 1936 work Language, Truth, and Logic, Ayer developed the verification principle, which states that there are only two types of statements that can be true or false: 1) a statement that can be verified or falsified by our sense experience (e.g., “It’s snowing outside”), and 2) a statement that is self-evidently true or false by the meaning of the words, called a tautology (e.g., “A bachelor is a single man”). If a statement fails to fit either of these categories, Ayer concludes it is metaphysical and neither true nor false but literally senseless.
It would seem that logical positivism has dealt a deathblow to theism. But such a deathblow is only apparent. Here are three ways we can respond.
Flunking the test
First, the verification principle is self-refuting, since it cannot be true based on the logical positivist’s own principles. Take the belief of logical positivism itself: a statement is meaningful only if it can be proven true or false by empirical investigation or if it’s a tautology. Can we prove this belief to be true or false by our sense experience? Is it a tautology?
With regard to empirical investigation: where is this belief found in the universe? How much does it weigh? Can we see its truth-value under a microscope? The absurdity of these questions proves that the belief cannot be verified or falsified by sense experience.
Nor is this belief a tautology. The meaning of the subject—“a statement”—is not contained in the predicate—“meaningful only if it can be proven true or false by empirical investigation, or if it’s a tautology.” This is a far cry from having the form of the assertion, “A bachelor is a single man.”
So, if the verification principle is neither empirically verifiable/falsifiable nor a tautology, then by its own criteria it is meaningless. As my philosophy classmate put it, “The verification principle can’t survive the verification principle.” It flunks its own test.
A “hooray” and “boo” type of morality
Another response to logical positivism is that it undermines morality. If a statement were meaningless because it can’t be empirically verified or falsified, or if it’s not a tautology, then any statement concerning morality would be meaningless.
To illustrate, the belief “unjust discrimination is wrong” cannot be verified or falsified by our sense experience, nor is it self-evidently true or false by the meaning of the words. Therefore, according to the verification principle, the statement “unjust discrimination is wrong” is meaningless. It makes no more sense than the phrase, “Shama lama ding-dong.” But that’s absurd!
No logic allowed
This leads to a third response: it undermines the logic of moral reasoning. For a logical positivist, the following syllogism:
P1: Every act that is unjust discrimination is bad.
P2: This act is an act of unjust discrimination.
Therefore, this act is bad.
translates to:
P1: Shama lama.
P2: This is an act of unjust discrimination.
Therefore, ding-dong.
If logical positivism were true, the former syllogism would be just as illogical and unintelligible as the latter. But clearly the former is logical and intelligible. Therefore, logical positivism is false.
An emotional consequence
Perhaps the logical positivist is not willing to say that moral judgments are completely meaningless, but just that they can’t be true or false. Ayer asserted that moral judgments are expressions of emotion intended to arouse similar feelings in others and stimulate action. This ethical theory is called emotivism, and Ayer embraced it because he saw it flowing directly from his logical positivism. If moral statements can be neither true nor false, but we must evaluate them somehow, and since humans make them all the time, they must be expressions of emotion.
To use Ayer’s example in his aforementioned work, if I say, “You acted wrongly in stealing that money,” the use of the word wrongly adds nothing to the literal meaning of the statement. As Ayer puts it, “The function of the ethical word is purely emotive” and “is used to express feeling about objects, not to make any assertion about them.”
If a logical positivist wants to dig his heels in and hold to this view, then there are two critiques we can offer in response.
Can’t argue with an emotion
First, emotivism is self-defeating. Inasmuch as an emotivist like Ayer attempts to argue for emotivism, he necessarily implies that one ought to believe it, given our nature as rational beings. Why else would he put forward an argument in support of it? But why should anyone take seriously the claim that emotivism is true if such an assertion is merely an expression of emotion (e.g., “hooray for emotivism”)?
We can also respond with a similar argument against logical positivism—namely, that it undermines logical reasoning itself. For an emotivist, the following syllogism:
P1: Every act that is unjust discrimination is bad.
P2: This act is an act of unjust discrimination.
Therefore, this act is bad.
translates to:
P 1: Every act that is unjust discrimination, “Boo!”
P 2: This act is an act of unjust discrimination.
Therefore, this act, “Boo!”
If emotivism were true, the former syllogism would be just as illogical and unintelligible as the latter. But clearly the former is logical and intelligible. Therefore, emotivism is false.
Sanity and sanctity
Obviously, this refutation of logical positivism doesn’t prove that God exists. Further philosophical investigation is required for that. But the refutation does show that the belief God exists is not meaningless and that philosophical investigation is possible.
The above refutation also shows how there are consequences to bad thinking. The demand for empirical verification or falsification for a belief leads to undermining morality itself.
This is not to say that all who embrace logical positivism are immoral people. But the logic embedded in logical positivism ultimately leads to the rational justification of immorality. If moral judgments are neither true nor false and are nothing more than emotional expressions, then there is nothing in principle to rationally justify the claim that any behavior is right or wrong.
It’s important that we get our thinking straight so we don’t get crooked in our behavior.