Propositional Fallacies
Propositional Fallacies arise from invalid logical relationships between statements, regardless of their content.
The Form
Errors involving “if,” “and,” “or,” and “not”
The logical structure itself is invalid
A Simple Example
“Either you agree with me, or you’re lying.”
This falsely limits the logical possibilities.
Why This Reasoning Fails
Even if each statement sounds reasonable on its own, the way they are connected violates valid logical rules.
Where it commonly appears
- Debates framed as binaries
- Ideological arguments
- Online discourse
- Moral absolutism
Example in god claims
“Either God exists, or nothing has meaning.”
The structure excludes other logical possibilities without justification.
How to avoid this fallacy
Ask:
Does the logical structure allow all reasonable alternatives?
Related concepts
- False Dilemma
- Logical Validity
- Truth Tables
OpenLogic Remainder
Sound conclusions require valid structure, not just confident phrasing.