Is 'Murder Is Wrong' Just Another Way of Saying 'Boo!'?
A Boy Who Demanded Proof
In 1923 a boy named Alfred Jules Ayer (1910–1989) arrived at Eton College. He was quick, competitive, and intensely irritating to his classmates. What annoyed them most was his relentless habit of trying to convert everyone to atheism. Ayer wasn’t just being rebellious — he had discovered a principle that would steer his entire life. Reading Bertrand Russell (1872–1970), he learned that it is undesirable to believe a proposition when there is no ground for believing its truth. For Ayer, that sentence became a motto. If a claim could not be backed up with solid reasons, you had no business believing it.
This rule sounded simple, but it lit a fuse under a whole mountain of philosophy, religion, and morality. Ayer followed it first to Oxford, where Gilbert Ryle (1900–1976) pointed him toward a group in Vienna who were also trying to scrub philosophy clean of unprovable claims. He spent a few months in 1933 sitting in on the Vienna Circle — a collection of thinkers around Moritz Schlick (1882–1936) and Rudolf Carnap (1891–1970) who were developing logical positivism. Ayer returned to England, wrote a book in a feverish burst, and by 1935 had published Language, Truth and Logic. It was a firecracker. It said, in effect, that huge chunks of what philosophers had been doing for centuries were literally meaningless. The central weapon was a tool he called the verification principle.
The Verification Exam
Ayer divided all meaningful statements into two tribes. On one side you have analytic statements — things that are true just because of the words inside them, like “All bachelors are unmarried.” Strip them down and they don’t tell you anything new about the world; they unpack the definitions. On the other side are synthetic statements — claims about the world that can be checked against sense experience. “There is a cat on the mat” is synthetic: you can look and see. According to Ayer, if a statement isn’t analytic, the only way it can be meaningful is if it is verifiable — if there is some possible observation that would show it to be true or false.
He first tried to capture this with strong verification, which demanded that the truth of a statement be conclusively proven by experience. But that was too strict: when do we ever conclusively prove anything? So he offered weak verification: a statement is meaningful if, together with some other auxiliary statements, you can deduce an observation statement from it that you couldn’t deduce from the auxiliaries alone. That way you didn’t need absolute certainty, only a link to possible experience.
Almost immediately, philosophers cooked up devastating counter‑examples. In 1949 Alonzo Church (1903–1995) showed a clever logical recipe that, if Ayer’s rules were accepted, seemed to make any random statement indirectly verifiable. Ayer kept patching the criterion, but no version ever became airtight. Yet he never abandoned the gut feeling behind it: meaning and possible evidence are tight partners. If your sentence floats free of all experience, what on earth are you talking about?
Moral Feelings, Not Facts
This is where the bombs went off. Apply the verification test to moral statements like “Stealing is wrong” or “Kindness is good.” Can you observe wrongness? Is there a scientific experiment that detects “good”? Ayer thought not. There is no empirical fact corresponding to these words — you cannot verify moral claims with your senses. If morality isn’t analytic and it isn’t verifiable, then, on his strict scheme, moral sentences are cognitively meaningless. But that didn’t mean they were gibberish. Ayer offered a new interpretation: emotivism.
When you say “Murder is wrong,” according to emotivism, you are not reporting a fact. You are expressing a feeling — a negative emotion toward murder — and perhaps encouraging others to share that feeling. Saying “Helping others is good” is like shouting “Hooray for kindness!” And calling something wrong is like saying “Boo!” to it. This was not, Ayer stressed, the same as saying “I feel bad about murder.” That would be a factual report about your own psychology, and it would be verifiable. Emotivism says moral language isn’t a report at all; it’s a direct emotional signal.
Critics pounced. If moral talk is just emotional outburst, why do we argue so carefully about right and wrong? One reply was that moral disputes are really about non‑moral facts — we agree about values but disagree about what actually happened — or they aren’t really disagreements at all, merely shouting matches. A deeper problem, later called the Frege‑G each problem, asks: if moral words just express feelings, how can they work inside complex arguments? In an “if … then …” sentence like “If John killed Jane, he did something wrong,” the word “wrong” doesn’t seem to carry any emotion; it just connects ideas. If emotivism can’t explain that ordinary logical move, maybe it misreads the very grammar of ethical life.
Is That a Table or Just Colors?
Ayer’s itch to ground meaning in experience pushed him toward an old, spiky problem. When you look at a table, what do you directly perceive? You probably think you see the table itself — a solid physical object. But Ayer thought experience teaches us otherwise. Stare at a straight stick in water: it looks bent. Look at a white wall under red lighting: it looks pink. In these illusions, nothing in the physical world corresponds to the bent‑stick or pink‑wall experience. So, Ayer reasoned, what you are directly aware of can’t be the physical object itself. It must be something mental — a sense‑datum (plural sense‑data). You only ever directly perceive sense‑data; the physical table is something you infer as the cause, a kind of theory you build to make sense of the shifting sensory show.
At first, Ayer even thought all statements about material objects could be translated into statements about actual and possible sense‑data — a view called phenomenalism. If successful, that would mean the physical world is reducible to a pattern of sensory experiences. He later backed away from that extreme: the translation project failed because statements about tables cover far more than any finite bundle of sensory claims. But he held onto the claim that our experience of the world is indirect. We inhabit a primary system of qualia — the raw colors, sounds, and textures — and we construct a secondary system of physical objects as an explanatory tool.
J. L. Austin (1911–1960), a philosopher with a famously sharp tongue, tore into this picture. In his lectures and in the book Sense and Sensibilia, Austin argued that Ayer’s entire setup relied on a mistaken use of the argument from illusion. Just because an illusion and a normal perception can seem alike doesn’t mean they are alike in their objects. Austin questioned whether there even is a neat border between “veridical” and “non‑veridical” perceptions, and he accused sense‑data theorists of inventing strange mental entities without good reason. For Austin, ordinary language already works perfectly well: we see tables, not private mental ghosts.
Ayer shot back that the argument from illusion was only one strand of the case, and he insisted that common‑sense judgments already go beyond what is “strictly available” in experience. The disagreement was about whether that gap demands a theoretical leap. He accepted that the inference is usually unconscious — but it is an inference nonetheless.
Why the Bombshell Still Echoes
Ayer spent his later decades refining his views. He softened his hostility toward metaphysics, allowing that a grand theory could serve as a useful conceptual framework — what he called a secondary system — so long as it had some explanatory value. He adjusted his theory of truth, shifting from a brash “true is redundant” slogan to a more careful deflationism. And he admitted that emotivism might not be the last word, even flirting with John Mackie’s error theory, which says moral language does aim at facts, but there simply are no such facts.
Why does any of this matter to you? Because you live inside the questions Ayer raised. When you call a classmate’s remark “mean,” are you stating a detectable property of the remark, or are you venting an emotion and inviting others to pile on? When a friend insists that a movie is “objectively terrible,” is there a hidden fact they can point to, or are they, in Ayer’s language, just booing loudly? And every time you trust your eyes to tell you what is real, you replay the puzzle of perception that Ayer and Austin thrashed out. His principle — that we should check what we claim against the evidence — sounds like common sense. But as his own struggles showed, drawing the boundary between evidence and nonsense is one of the hardest jobs in philosophy.
Think about it
- If you say “Pineapple on pizza is disgusting,” are you stating a fact or just expressing your taste? How would you tell the difference?
- Suppose a supercomputer could predict every choice you will ever make. Would it still be fair to praise or blame people for what they do?
- Try to describe the taste of chocolate without using words like “sweet,” “smooth,” or “good.” Are there limits to language that mean some experiences can never be captured by facts alone?
