Are You Pretending When You Say 'Two Plus Two Is Four'?
When Serious Things Sound Like a Game
Imagine your math teacher asks, “Does the number seven exist?” You might roll your eyes and say, “Of course it does. Seven is prime. It’s an odd number. You can add it to eight to make fifteen.” But a philosopher might push further: “Where is seven? Can you touch it? Is it like a chair or a dog?” Suddenly, the question feels less obvious.
Some philosophers answer by saying that when we talk about numbers, we are not really trying to describe a hidden world of invisible objects. Instead, we are engaging in a kind of useful make‑believe. This view is called fictionalism. A fictionalist thinks that a whole area of talk — whether math, morality, or even everyday objects — is a fiction: the things we say are not literally true, but they are worth saying anyway, because pretending they are true helps us get around in the world. You can think of it like a board game. When you land on Park Place and pay rent, you do not believe there is a real hotel. You just follow the rules of the game. That gets the job done.
The idea is not new. The legal thinker Jeremy Bentham (1748–1832) argued that much ordinary talk refers to “fictitious” entities. The philosopher Hans Vaihinger (1852–1933) built a whole system around the phrase “as if” — we live as if many things are true, without needing them to be really real. Even Voltaire’s quip “If God did not exist, it would be necessary to invent him” captures a fictionalist spirit toward religion. Today, fictionalism is a general strategy. Instead of fighting about whether numbers or moral facts exist, you can ask: what if we are already, in some sense, only playing along?
Are We Already Pretending, or Should We Start?
Not all fictionalists agree on what is going on right now. Some say we have been speaking fictionally all along without realizing it. This is called hermeneutic fictionalism. If hermeneutic fictionalism about math is correct, then even when you are doing your homework, you are not literally asserting that there are numbers. You are engaging in a pretense, much like when you say “the average family has 2.5 children” — the sentence is useful, but nobody thinks there is a fractional half‑child skipping around. Other fictionalists take a different path. According to revolutionary fictionalism, we do speak literally at the moment, and we really do believe that numbers exist. But we shouldn’t. We should change our practice: we should keep using the same sentences, but shift to a make‑believe attitude, because it would give us all the benefits without having to commit to the existence of numbers.
The philosopher Hartry Field, in a book from 1980, argued for a revolutionary fictionalism about mathematics. He thought that even though mathematical sentences are not literally true, they are an invaluable tool for making predictions about the world. As long as they never lead us to a false conclusion about the non‑mathematical things we can see and touch, we do not need to believe them. The moral philosopher Richard Joyce has defended a similar view about ethics. He suggests that even if nothing is objectively right or wrong, pretending that moral rules are real can help us resist temptation and cooperate with others — just like a scary story can keep a camper from wandering into the woods at night.
So fictionalism splits into two big camps. Hermeneutic fictionalists say we are already inside the game; revolutionaries say we should start playing it on purpose.
The Oracle and Other Reasons to Doubt Reality
Why would anyone think fictionalism is true? One striking argument comes from a thought experiment. Suppose a creature you are absolutely certain is an all‑knowing Oracle tells you that there are no abstract objects — no numbers, no properties, no possible worlds. After you pick your jaw up off the floor, would you stop talking about the number seventeen? Would you refuse to say “You can’t divide seventeen evenly”? Almost certainly not. You would carry on just as before. That suggests something important: maybe you never really believed in numbers in the first place. Your words were already working inside a fiction.
Another puzzle is the paradox of existence. In the philosophy classroom, the question “Do numbers exist?” feels deep and hard. But in everyday life, we slip into easy proofs. You say “2+2=4, so there is a number that, when added to 2, gives 4. Therefore numbers exist.” That sounds trivial. How can the same question be both glaringly obvious and fiercely debated? A fictionalist has a neat answer: outside the classroom you are speaking inside a fiction, where “numbers exist” is true‑in‑the‑game. But when you step back and speak literally, the claim becomes a genuine mystery.
Fictionalists also point to how often we use non‑literal talk without noticing. We say the sun rises, even though we know it’s the Earth that turns. We discuss the average American, even though nobody in the room is exactly 5’4” with a blend of all political views. The philosopher Stephen Yablo has listed dozens of unobtrusive metaphors — phrases like “something tells me you’re right” or “there’s no precedent for that” — that we use every day without any sense that we are inventing objects. If our speech is already drenched in harmless make‑believe, maybe talk about numbers or moral properties is just more of the same.
What Critics Say: “This Isn’t a Fairy Tale!”
The most immediate objection to fictionalism is that it just feels wrong. Mathematical discourse does not seem like a fairy tale. When you work out a proof, you feel like you are discovering something real, not inventing a story. The philosopher Jason Stanley has sharpened this worry. He argues that if hermeneutic fictionalism were true, people would be in a state of pretense without being able to tell — a drastic failure of knowing your own mind. He also notes that autistic individuals often have trouble with pretend play, but they do not have trouble with math or modal reasoning. If math were really a game of make‑believe, we would expect them to struggle with it. They don’t.
Another challenge concerns systematicity. You can understand and produce a huge number of mathematical sentences, even ones you have never heard before. How do you do that, if the sentences do not have their usual literal meanings? A fictionalist must explain how the pretense works in a rule‑governed way. Yablo replies that we already understand irony, hyperbole, and metaphor without a compositional theory, so maybe math‑talk can work in a loosely similar fashion. But critics reply that those forms of speech are not quite the same — they are uses of language, not a whole new layer of meaning.
Some object that fictionalism does not truly escape ontological commitment. The Brock‑Rosen objection (originally aimed at fictionalism about possible worlds) shows that a fictionalist who defines truth as “according to the fiction, p” can sometimes be forced, by logical steps, into saying something literally true that they wanted to avoid. A common fix is to insist that fictionalism is only a claim about how we use language in ordinary life, not about a new theory of meaning. That helps, but it also limits how much the fictionalist can promise.
Why It Matters: What Exists and How We Talk
Fictionalism is not just a strange idea — it is a powerful lens. Many arguments in philosophy try to prove that something exists by pointing to the way we speak. An ordinary language argument goes like this: “We say things like ‘Stealing is wrong.’ For that sentence to be true, there must be moral facts. So moral facts exist.” But if fictionalism is on the table, that move becomes shaky. Maybe we do not need the sentence to be literally true; we just need it to be useful inside a fiction. Fictionalism acts like a giant permission slip: you can keep talking the way you do, without having to believe in a hidden realm of abstract objects or moral properties.
It also rattles a whole approach to ontology — the study of what exists — that was made famous by the philosopher W.V.O. Quine. Quine said we should believe in whatever our best scientific theories say exists. But Yablo points out that this depends on being able to tell which parts of our theories are meant literally and which are not. What if we cannot always tell? If the line between literal and fictional speech is blurry, then the project of reading off reality from our sentences becomes much harder.
You may already be a quiet fictionalist in your everyday life. When you say “the sun rose at 6:03,” you are not a flat‑earther. You are just using a convenient, centuries‑old way of speaking. When you discuss what a character in a video game should do, you may not believe the character has real free will, but the pretense lets you think clearly about strategy. The fictionalist says we can extend this attitude to large chunks of our talk — and that doing so might be more honest than insisting everything we say must pin down a real piece of the world.
Think about it
- If you say “SpongeBob lives in a pineapple,” is that a lie, or are you just talking inside a story? Does it feel different from saying “The sun rises”?
- Suppose a friend tells you “Stealing is wrong,” but then adds, “I don’t believe moral rules are real facts — I just find it useful to pretend.” Could you still take your friend seriously? Why or why not?
- Can you think of something you talk about every day that might be a fiction, even though everyone around you acts like it is real? How would you test whether it’s really a fiction?
