Illicit Major

📐

Illicit Minor

Logically close Same family Similar wording

Draws a syllogistic conclusion that distributes the minor term more broadly than the premises allow.

🔺

Undistributed Middle

Logically close Same family Similar wording

Uses a shared middle term in a syllogism without properly connecting the categories, so the conclusion does not follow.

📚

Syllogistic Fallacies

Logically close Same family Similar wording

Uses a broken syllogism or category relationship so the conclusion does not logically follow.

4️⃣

Four-Term Fallacy

Same family Similar wording Same category

Uses a syllogism with four terms instead of three, often because a key term shifts meaning.

🔢

Quantification Fallacies

Same family Often confused Similar wording

Misuses words like all, some, or none so the conclusion goes beyond what the premises support.

∴

Propositional Fallacies

Same family Similar wording Same category

A broader label for invalid moves in propositional logic where the conclusion does not validly follow from the premises.