How to spot circular reasoning?

On the philosophy of circular reasoning and how to spot it in everyday conversations...

gem

Sep 05, 2025

When you're a philosophy student, you're taught to stay far away from circular reasoning. It's this sneaky, seductive trap that sounds convincing until you realise the argument is basically a snake eating its own tail.

Now, as someone wandering through the world (especially online), I don't trust half the things people write. There's something superficial about so much of what passes for argument these days, something that lacks real substance or intellectual rigour. More often than not, it's because people are trapped in circular reasoning without even realising it.

Circular reasoning is a logical fallacy where the argument's conclusion is assumed in its premise. The person making the argument uses what they're trying to prove as part of their proof, which is about as useful as trying to lift yourself up by your own bootstraps. Aristotle called this petitio principii , and contemporary philosophers discuss epistemic circularity, but the basic problem remains the same: the conclusion and premise end up depending on each other in a way that proves absolutely nothing.

The ontological argument is perhaps the most famous example of circular reasoning masquerading as sophisticated philosophy. Originally proposed by Anselm of Canterbury in the 11th century, the argument goes something like this: God is defined as the greatest conceivable being, and since existence is greater than non-existence, God must exist because a non-existent God wouldn't be the greatest conceivable being. See the problem?

The argument assumes God's existence (as "the greatest conceivable being") in order to prove God's existence. It's essentially saying "God exists because God is the kind of thing that exists," which proves absolutely nothing. Philosophers have been picking apart this argument for centuries. Kant famously argued that existence isn't a predicate, but it keeps resurfacing because it sounds impressively logical until you realise it's just an elaborate way of stating your conclusion as your premise. It's the philosophical equivalent of saying "I'm right because I'm right," dressed up in enough theological language to make it seem profound.

Of course, it's not every day someone cites the ontological argument in casual conversation, but these types of flawed reasoning patterns show up constantly in everyday discussions. You know something feels wrong with what they're saying, but their argument sounds right on the surface. You're left feeling frustrated and unable to articulate exactly why their logic doesn't hold water.

Here's how to identify circular reasoning and, frankly, how to run away from people who use it regularly, because it becomes genuinely toxic after a while.

1. The Conclusion Just Repeats the Premise

Watch for arguments that simply restate their conclusion in different words. If someone's logic boils down to "X is true because X is true," you're dealing with pure circularity. They might dress it up with more elaborate language, but underneath it's just the same claim repeated back to you as if repetition equals proof.

2. Key Terms Define Themselves

Notice when important concepts are being defined by the very thing they're supposed to explain. It's like saying "happiness is good because it makes you happy." You're not actually learning what happiness is or why it might be valuable; you're just going in circles.

3. Authoritative Repetition Without Evidence

Be wary when people rely heavily on claims like "everyone knows this" or "everyone needs to read this" (ugh, I hate that phrase). They're trying to make their argument seem more solid by appealing to some imaginary consensus rather than actually providing evidence or reasoning.

4. Flowery Language Hiding Weak Logic

Step away from the jargon and strip the language back to basics. Are they dressing up a fundamentally flawed argument in impressive-sounding terminology? Because that's usually what's happening when something sounds sophisticated but leaves you feeling confused rather than enlightened.

The internet has made circular reasoning epidemic. People throw around impressive-sounding arguments that collapse the moment you examine their structure, but by then they've already moved on to the next impressive-sounding claim. Learning to spot this pattern isn't just about winning debates; it's about protecting your own thinking from getting tangled up in other people's intellectual knots.