Conflicting Conditions (Contradictio in Adjecto)
A logical fallacy in which an argument contains a self-contradiction, making it impossible for it to be true. It occurs when the argument asserts something that contradicts its own terms or conditions.
THE IDEA
Conflicting Conditions (contradictio in adjecto)
Also known as: a self-contradiction
Description
When the argument is self-contradictory and cannot possibly be true.
Examples
- Example #1: Being certain that a question remains unsettled is not automatically self-contradictory. The certainty concerns the state of knowledge, not a settled answer to the question.
- Example #2: “I don’t care what you believe, as long as it doesn’t harm others.” The phrase “as long as” restricts the assertion to beliefs that do not harm others. A statement with that condition is not automatically a contradiction.
Exception
When the self-contradictory statement is not put forth as an argument, but rather as an ironic statement, perhaps with the intent to convey some kind of deeper truth or meaning, but not to necessarily be taken literally, then this fallacy is not committed.
When to use it
Checking political slogans for internal consistency.
Evaluating scientific hypotheses for self-contradictory assumptions.
Analyzing rhetorical speeches for logical flaws.
Identifying flawed reasoning in everyday debates or discussions.
FROM THEORY TO EVERYDAY LIFE
In practice
Uncertainty cannot be certain
Being certain that the available evidence does not settle a question is different from claiming both that an answer is certain and that the same answer is uncertain. The first does not by itself demonstrate a contradiction.
I don't care what you believe, as long as it doesn't harm others
The phrase "as long as" limits the claim to beliefs that do not harm others. Caring whether that condition holds does not itself contradict the conditional claim.
A MOMENT TO REFLECT
Put it to work.
Can you think of a common saying or slogan that contradicts itself?
How can you identify self-contradictory arguments in political or media statements?
Why is it important to avoid self-contradiction when constructing a logical argument?
CONTINUE THE CONVERSATION
Source texts
- Logically Fallacious - The Ultimate Collection of Over 300 Logical Fallacies