Statement of Conversion
The fallacy of accepting a person's change of mind as valid evidence for a claim, without considering the reasons behind the conversion.
THE IDEA
Description
Taking a statement of conversion as valid without actually hearing a reason for the conversion.
Logical Form
- Person A changed their mind about X.
- Therefore, X is true/false (depending on the direction of conversion).
Examples
Example #1: A person who was a Christian becomes an atheist and uses that conversion as evidence against Christianity. Explanation: All this tells us is that the arguer changed his mind. We don’t know why. Accepting this as evidence against Christianity would be fallacious reasoning.
Example #2: A person who was an atheist becomes a Christian and uses that conversion as evidence for Christianity. Explanation: All this tells us is that the arguer changed his mind. We don’t know why. Accepting this as evidence for Christianity would be fallacious reasoning.
Exception
A person’s relevant expertise may give their revised judgment some evidential weight. The weight depends on that expertise and the reasons for the change; the conversion alone does not prove the claim.
When to use it
A political candidate changes their position on a key issue and uses their conversion to argue for their new position without providing reasons.
A friend switches from one diet to another and claims the new diet is superior simply because they changed their mind.
In a debate, someone cites a famous person's conversion to a particular ideology as proof of that ideology's correctness.
FROM THEORY TO EVERYDAY LIFE
In practice
Conversion from Christianity to Atheism
A former Christian becomes an atheist and uses that conversion as evidence against Christianity. Explanation: All this tells us is that the arguer changed his mind. We don’t know why. Accepting this as evidence against Christianity would be fallacious reasoning.
Conversion from Atheism to Christianity
A former atheist becomes a Christian and uses that conversion as evidence for Christianity. Explanation: All this tells us is that the arguer changed his mind. We don’t know why. Accepting this as evidence for Christianity would be fallacious reasoning.
A MOMENT TO REFLECT
Put it to work.
Why is a simple change of mind insufficient as evidence for the truth of a claim?
In what contexts might a conversion story be valid evidence?
How can you distinguish between a fallacious appeal to conversion and a legitimate appeal to expert opinion?
CONTINUE THE CONVERSATION
Source texts
- Logically Fallacious - The Ultimate Collection of Over 300 Logical Fallacies