Enthymeme
Pattern
Conclusion + one premise — missing premise assumed
Definition
A syllogism with one premise left unstated because it is assumed to be obvious or widely accepted.
Examples
Example 1
She must be a good leader — she won by a landslide.
The suppressed premise is "winning by a landslide indicates good leadership" — left for the audience to supply
Example 2
Of course he's guilty — he ran from the police.
The hidden premise is "innocent people don't run" — persuasive precisely because the assumption goes unexamined
Example 3
We should ban the chemical — it causes cancer.
The suppressed major premise ("things that cause cancer should be banned") makes the argument feel self-evident
AI Detection Note
AI tends to state all premises explicitly rather than leaving one unstated. LLMs are biased toward completeness and clarity, making the deliberate omission of a shared assumption uncommon in AI text.
See how your writing uses this figure
Analyze Your Text