Circularity occurs when an argument assumes what it is trying to prove. Instead of providing evidence for a conclusion, the premises already contain or depend on that conclusion.
Circular argument:
- The newspaper is trustworthy because it always reports the truth.
- We know it reports the truth because it is trustworthy.
The argument goes in a circle and provides no independent support.
To avoid circularity:
- Premises should provide evidence, not assume the conclusion.
- Premises should be independently justified.
- A person should be able to accept the premises while still questioning the conclusion.
- Avoid merely restating the conclusion in different words.
- Look for hidden assumptions that already contain the claim being argued for.
A useful test is:
Can someone reasonably accept the premises while rejecting the conclusion?
If the answer is no, the argument is likely circular.
Good reasoning moves forward by adding support. Circular reasoning simply returns to where it started.