Comparison guide
Circular Reasoning vs. Weak or Missing Evidence
Circular reasoning gives a reason that assumes or restates the conclusion; weak evidence is independent of the conclusion but simply not strong enough.
Side by side
| Question | Circular Reasoning | Weak or Missing Evidence |
|---|---|---|
| Is the reason independent of the conclusion? | No, it reuses the conclusion | Usually yes, but it is inadequate |
| Example | It is reliable because it can be relied upon. | It is reliable because one person liked it. |
| What the argument is missing | Any support outside the claim itself | Enough relevant, sufficient support |
| Repair | Add genuinely independent evidence | Add more relevant and sufficient evidence |
Which one is it?
Fits Circular Reasoning
"This rule is the best because no better rule exists, and we know no better rule exists because this one is the best."
Fits Weak or Missing Evidence
"This rule is best because one student said so." The reason is independent but far too thin.
Could fit both
An argument can restate its conclusion once and then add a single weak reason, showing traces of each problem.
Fits neither
"The rule improved the stated outcome across several comparable trials and produced fewer side effects than the alternatives."
A decision path
- Does the reason stand on its own, or does it reuse the conclusion?
- If it is independent, is it relevant to the claim?
- Is there enough of it for a conclusion this broad?
- What additional evidence would strengthen the argument?
Read the full pages
- Circular Reasoning
- Weak or Missing Evidence is a contrast concept, not one of the 15 project topics.