How Words Shape Our Thinking: Al-Fārābī on Language, Logic, and the Mind

Imagine you’re part of a small group of people who have never spoken a single word. You have thoughts. You notice things around you—rocks, trees, other people, fire. You can point at things to get someone’s attention. You can grunt to show you need help. But you have no words.

Now imagine that someone in your group decides this isn’t working well enough. So you all agree on some sounds: “water” for that wet stuff you drink, “fire” for the warm orange thing, “run” for moving fast. Pretty soon you have a whole collection of sounds that stand for things in your mind. You have a language.

This is roughly the picture that a philosopher named Al-Fārābī painted over a thousand years ago, living in what is now Iraq and Syria. He wanted to understand something strange and important: how does language connect to thinking? And if language and thinking don’t match up perfectly, does that cause problems?

The Puzzle of Mismatched Words

Here’s a weird thing Al-Fārābī noticed. Words and concepts (the ideas in your head) don’t always line up neatly. For example, in Arabic there’s a word mawjūd which grammatically looks like it should mean “something that was found” (like a lost wallet). But people use it to mean “is” or “exists.” That’s a mismatch—the word’s shape suggests one kind of meaning, but it’s used for something else entirely.

Al-Fārābī thought this was a real problem. Not a small problem, like “people might get confused sometimes.” A bigger problem. Because if the relationships between words don’t mirror the relationships between ideas, then when you try to reason using words, you might make mistakes. Your logic could go wrong because your language is leading you astray.

Think about it this way. Imagine two ideas that are connected: “animal” is a bigger category that includes “human.” If our language had two words that looked totally unrelated—like if “animal” was blurg and “human” was zando—you’d never be able to tell from hearing the words that one contains the other. You’d just have to memorize that fact. But if the language made the connection visible—like “animal” and “humanimal”—you’d see the relationship right away.

Al-Fārābī wanted language to be a mirror of the mind. When it wasn’t, he worried, teachers couldn’t pass knowledge reliably to students, and logical arguments might not work properly.

How Language Gets Born

Al-Fārābī’s story about how language starts is surprisingly detailed. First, people have what he called “primary concepts”—basic ideas that come from experiencing the world. Things like “human,” “stone,” “walking,” “white.” These aren’t words yet; they’re just patterns in your mind.

Then somebody—Al-Fārābī says usually a lawmaker or leader—gets people to agree on sounds for these concepts. This is completely made up, by the way; nobody actually decided one day to invent language. Al-Fārābī knew that. He was telling a “just-so story” to explain how words and meanings relate, not a historical account.

Once you have words, something interesting happens. People start noticing that some of their concepts are similar to each other. So they try to make the words similar too. This is why we have words like “run” and “runner”—the concepts are related, and so are the words.

But here’s where it gets complicated. This process of matching words to concepts can go wrong. Sometimes two different concepts end up with the same word (that’s homonymy, like “bat” meaning both an animal and a sports thing). Sometimes a word that should be derived from another word isn’t, or vice versa.

Al-Fārābī thought these mismatches were bad, but he wasn’t angry about them. He didn’t try to reform language. He just pointed out that philosophers need to be careful.

The Secondary Concepts: Thinking About Thinking

Once people have language, they start doing something new. They start thinking about their own thoughts. This gives birth to what Al-Fārābī called “secondary concepts.” These are concepts about other concepts—like “genus,” “species,” “definition,” “predicate,” “subject.”

(You might notice this can go on forever: you can have concepts about concepts about concepts. Al-Fārābī knew this. He called them tertiary, quaternary, and so on. But he thought the same rules applied at every level.)

Here’s why this matters. The art of logic, Al-Fārābī says, is the study of primary concepts under a special set of features: how they get expressed in words, how they function as subjects and predicates, how they get defined in terms of each other, how they can be asked about. Logic doesn’t care what a stone is—that’s for natural science. Logic cares about how “stone” functions in sentences like “No stone is an animal” or “Some stones are heavy.”

This is a genuinely subtle idea. Logic, for Al-Fārābī, isn’t just a bunch of rules about arguments. It’s the study of concepts from a particular angle—the angle of how they can be combined, questioned, and used to draw conclusions.

Why We Need Different Kinds of Reasoning

Al-Fārābī thought about language and logic partly because he wanted to understand how people persuade each other. He noticed that we use different kinds of reasoning in different situations.

Rhetoric is what you use when you need to get a group of people to agree with you or do something. You pick premises your audience will accept. (Al-Fārābī even thought that a lot of what doctors and farmers do counts as rhetoric—because you can’t prove with absolute certainty that this medicine will cure this patient; you just have to reason from what usually works.)

Dialectic is what happens when two people disagree and need to sort it out through debate. One person asks questions, the other answers. The questioner tries to get the responder to commit to statements, then tries to show that those statements lead to a contradiction. This isn’t about finding absolute truth; it’s about who can make a better case.

Demonstration is the gold standard. This is reasoning that starts from true premises and gives you certainty. Al-Fārābī thought Plato was the first person to really grasp what demonstration was, but Aristotle was the one who wrote down the rules for it. Demonstration uses the kind of airtight syllogisms where, if the premises are true, the conclusion absolutely must be true.

But here’s the thing Al-Fārābī noticed: most human reasoning isn’t demonstrative. Most of the time we’re using rhetoric or dialectic or something in between. And that’s okay—as long as we understand what we’re doing and don’t demand more certainty than the situation allows.

The Syllogism Machine

You’ve probably heard of syllogisms before: “All humans are mortal. Socrates is human. Therefore Socrates is mortal.” That’s a categorical syllogism—it works with categories (all humans, some animals, no stones).

Al-Fārābī wrote a lot about these. He recognized three different “figures” of categorical syllogisms (different arrangements of the terms) and figured out which combinations of premises gave valid conclusions.

But he also worked on other kinds of reasoning. Hypothetical syllogisms involve “if…then” statements: “If it’s a human, then it’s an animal. It’s a human. Therefore it’s an animal.” Or “either/or” statements: “This number is either even or odd. It’s even. Therefore it’s not odd.”

Al-Fārābī even chained these together to make compound arguments, like a logical machine with multiple parts.

One interesting thing: Al-Fārābī thought that in many practical fields—medicine, agriculture, navigation—people treat “necessarily every A is a B” and “most A’s are B’s” as basically the same thing. This seems sloppy if you’re a pure logician, but it makes sense if you’re a doctor trying to save a patient. You don’t need absolute certainty; you need a good bet.

True, False, and the Future

What does it mean for something to be true? Al-Fārābī had an interesting answer. A concept is true if it’s the same in your mind as it is in the external world. So the concept “horse” is true because there really are horses out there, and your concept of a horse matches what horses actually are. But the concept “vacuum” (empty space with nothing in it) is not true—at least for Al-Fārābī—because it exists only in your mind, not in reality.

Notice that this means concepts can be true even if they aren’t put into sentences. A definition can be true. A single idea can be true. This is different from how many philosophers think about truth today, but it makes a certain kind of sense.

Al-Fārābī also had things to say about the future. Imagine a battle that will either happen tomorrow or not. Right now, is it true that the battle will happen? Is it true that it won’t? Al-Fārābī said neither. The future is genuinely open. Even if God knows what will happen, that doesn’t mean it’s already determined. (This got him into difficult theological territory, and he didn’t fully resolve the tension.)

This part gets technical, but here’s what it accomplishes: it preserves the idea that humans have real choices. If everything about the future were already true right now, then you wouldn’t really be deciding anything—you’d just be unfolding what was already written. Al-Fārābī wanted to keep space for freedom.

The Language That Almost Works

One of Al-Fārābī’s more unusual projects was comparing Arabic to other languages. He didn’t actually know Greek (he made some mistakes when talking about it), but he used Greek as an “ideal” logical language—a language where the grammar always matches the logic.

Here’s the basic idea. In a perfect logical language, words for simple concepts would be simple words, and words for derived concepts would be derived from the simple ones. The copula (“is”) would be a separate word, not hidden inside a verb. Tenses would work cleanly. There would be no confusing homonyms.

Arabic, Al-Fārābī noticed, doesn’t always do this. But neither does any actual language. What he was doing was using the comparison to highlight where Arabic succeeds and fails at mirroring the structure of thought.

One of his best linguistic insights: you can’t really make a verb out of “human” in Arabic, he said, because “human” is a permanent property. Verbs describe things that happen or change. If you try to make a verb from “human,” you get something like “become a human”—which makes sense because becoming is a change. This is genuinely subtle observation about how language reflects our understanding of the world.

Poetry and the Almost-Syllogism

This is where Al-Fārābī gets really interesting. He thought poetry was a kind of logic. Not the strict demonstrative kind, but something that works on our imagination.

Consider a line of Arabic poetry: “Knowledge lies in the bright spears gleaming between two armies.” What does this mean? Literally it’s nonsense—knowledge isn’t really in spears. But Al-Fārābī says we can expand it into an almost-syllogism:

The spears give certainty. Knowledge gives certainty. Therefore the spears are knowledge.

This isn’t a valid deductive argument. The conclusion doesn’t follow from the premises. But that’s not the point. The point is that the poem makes you think of that connection. It works on your imagination, not on your logic.

Al-Fārābī called poetic premises “absolutely false,” which seems harsh. But he later softened this, saying that poetry doesn’t aim to tell truth or lies—it aims to stir the soul. A poem can be false in the literal sense and still contain “poetic truth” that changes how you see the world.

Why This Still Matters

Al-Fārābī’s big question—how do language and thinking relate to each other?—is still alive today. Every time you notice that two different languages carve up the world differently (some languages have no word for “blue” as separate from “green”; some have multiple words for “snow”), you’re dealing with the same puzzle Al-Fārābī was exploring.

And his insight that most of our reasoning is rhetorical or dialectical rather than demonstrative is deeply practical. When you argue with a friend about who should do the dishes, you’re not doing mathematics. You’re using premises you hope your friend will accept, trying to get them to see your point. That’s rhetoric. When a teacher explains something and you ask questions to test whether the explanation holds up, that’s dialectic.

Al-Fārābī thought these weren’t inferior forms of reasoning. They were what humans actually do, and understanding their rules could make us better at thinking and communicating. Not bad for someone writing a thousand years ago.

Key Terms

Term	What it does in this debate
Primary concepts	The basic ideas we get from experiencing the world—like “human,” “stone,” “white”—before we put them into words
Secondary concepts	Concepts about other concepts—like “genus,” “species,” “predicate”—that let us think about thinking
Syllogism	A structured argument where two premises lead to a conclusion; the basic unit of logical reasoning for Al-Fārābī
Demonstration	The highest kind of reasoning, which starts from true premises and gives certainty
Rhetoric	Reasoning that aims to persuade, using premises the audience will accept rather than absolutely true ones
Dialectic	The art of debating and resolving disagreements through question-and-answer, without guaranteeing truth
Copula	The “is” that connects subject and predicate in a sentence—like the glue that holds a statement together

Key People

Al-Fārābī (c. 870–950): A philosopher from Central Asia who wrote about logic, language, music, politics, and metaphysics, and who tried to combine the ideas of Aristotle with Islamic thought. He believed language and logic are deeply connected, and that most human reasoning isn’t about absolute certainty.
Aristotle (384–322 BCE): A Greek philosopher whose logical writings were the foundation of everything Al-Fārābī did. Al-Fārābī thought Aristotle had discovered the universal rules of demonstrative reasoning.
Plato (c. 428–348 BCE): Another Greek philosopher who, according to Al-Fārābī, was the first to recognize that demonstration was different from other kinds of reasoning—but he didn’t write down the rules for it.

Things to Think About

Al-Fārābī thought that words should mirror the relationships between concepts. But what if the way we think is partly shaped by what words are available? If you grow up speaking a language without a word for a certain idea, does that idea become harder to think? Or do we think first and find words second?
Most of our daily reasoning isn’t demonstrative—we don’t prove things with absolute certainty. So how do we decide when to trust someone’s argument? If a doctor can’t prove the medicine will work, but has good reasons to think it probably will, is that enough? What would Al-Fārābī say?
Al-Fārābī thought poetry was a kind of logic that works on the imagination. But if poetic “arguments” are invalid (the conclusion doesn’t actually follow from the premises), is it really reasoning at all? Can something be persuasive without being logical?
The idea that concepts can be true or false without being put into sentences seems weird. Is “horse” true? Is “unicorn” false? What about “justice”? If concepts can be true, how do we check?

Where This Shows Up

Programming languages are designed to mirror the structure of computation—very much like Al-Fārābī wanted natural languages to mirror the structure of thought. The idea of a “well-formed formula” in logic or code traces back to this kind of thinking.
Debate clubs and mock trials use exactly the dialectical structure Al-Fārābī described: one person asks questions, the other answers, and the goal is to show contradictions or weak spots in the other person’s position.
Cognitive linguistics studies how different languages shape different ways of thinking—exactly the kind of question Al-Fārābī was asking about Arabic and Greek.
Political speeches use rhetorical reasoning: they don’t prove things, but pick premises the audience already believes and draw conclusions from them. Understanding this helps you not get fooled by bad arguments dressed up in fancy words.