Argument Detective A Field Guide to 15 Logical Fallacies
#7 of 15 Make an Unsupported Leap

Circular Reasoning

Also called: begging the question, conclusion in premise, restated claim

Circular reasoning uses the conclusion itself, restated or assumed, as the reason for believing the conclusion.

A careful definition

An argument is circular when its support cannot be accepted without already accepting what the argument is trying to prove. Sometimes the conclusion is repeated in different words. Sometimes a hidden premise quietly assumes it. Either way, the reasoning never reaches independent evidence.

Family — Make an Unsupported Leap: Does the conclusion actually follow from the reasons?

The move

  1. Claim X is true.
  2. Give a reason that means "X is true" or depends on X already being true.
  3. Return to X without any independent support.

Why it can feel convincing

  • Rephrasing a claim can sound like explaining it.
  • Familiar assumptions may slip by unnoticed.
  • Repetition creates a feeling of certainty.

Clear examples, diagnosed

Clear example

The best captain

"I should be team captain because I am the best choice for captain. I know I am the best choice because I should be captain."

What went wrong:

  • The reason for being captain is being the best choice.
  • The reason for being the best choice is that they should be captain.
  • No independent qualifications, such as leadership or attendance, are supplied.
Repaired: "I should be captain because I have led three successful projects, resolve conflicts calmly, and attend every practice."

Clear example

The self-certifying website

"This website is always accurate because its own About page says everything on the website is accurate."

What went wrong:

  • The claim is that the site is accurate.
  • The evidence is the site's own statement that it is accurate.
  • The source is being used to prove its own reliability.
Repaired: "To judge whether the website is accurate, let us check its claims against independent sources and see whether experts confirm them."

Where the boundary is

Not a fallacy

Independent reasons

"Nora is a strong captain candidate because she has led three successful projects, resolves conflicts calmly, and attends every practice."

These reasons can be checked without already assuming the conclusion. A separate case is a definition, not an argument: "A triangle has three sides because a triangle is defined as a three-sided polygon" explains a meaning rather than trying to prove an uncertain claim.

Borderline case

A system with internal cross-checks

A trusted system claims to be reliable because its own internal checks agree with each other.

Questions to ask:

  • Is the supporting information genuinely independent of the claim?
  • Or is each "check" just another form of the same statement?
  • What outside evidence would break the circle if it exists?

Not automatically fallacious when

  • A statement is giving a definition rather than proving an uncertain claim.
  • Several premises support each other within a larger network that also connects to independent evidence.
  • The goal is clarification rather than proof.

Diagnostic questions

  • Could a person accept the reason without already accepting the conclusion?
  • Is the reason merely a synonym or restatement of the claim?
  • What outside evidence would break the circle?
  • Is this an argument at all, or simply a definition?

Spot it. Prove it. Repair it.

The argument

"The new rule is fair because it is a fair rule for everyone."

Spot Notice the possible problem

This looks like circular reasoning.

Prove Point to the exact failure

  • The claim is that the rule is fair.
  • The reason restates that the rule is fair.
  • No independent standard of fairness is offered.

Repair Rebuild it fairly

Repaired: "Let us define what fairness means here and show evidence about how the rule treats different groups and situations."

Use this for your project

Essential question

How can an argument sound like proof while never leaving the circle of its own claim?

Where to hunt for examples

  • Slogans and mottos that restate themselves.
  • Reviews or ads that call a product "the best because it is the best."
  • Rules justified only by repeating the rule.
  • Fictional characters who argue in circles.

Questions to research

  • What is the exact conclusion?
  • What reason is given for it?
  • Does the reason simply restate or assume the conclusion?
  • What independent evidence would be needed?

Project products to try

  • A diagram of arrows that loop back without reaching evidence.
  • A "break the circle" activity that adds an independent evidence branch.
  • A before-and-after showing a restatement replaced by real reasons.
  • A short skit exposing a circular claim.
Appeal to Authority

A self-certifying source is circular; an appeal to authority borrows an outside source's status.

Bandwagon

Both can feel like proof without independent evidence, one by repetition and one by popularity.

Hasty Generalization

Circular reasoning reuses the conclusion; hasty generalization jumps to it from too little evidence.

Sources and attribution

Content status: Original to this project. This page's explanations, examples, non-example, borderline case, and repair activity were written for Argument Detective.

Sources and further reading