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Our Logic is Better Than Yours

Have you ever heard an argument that didn’t seem right? Maybe you disagreed with the speaker’s logic but couldn’t put your finger on the problem. You likely encountered a “logical fallacy,” which is an occurrence of bad or incorrect reasoning. Explore this site to learn more about all the informal fallacies you may encounter! Once you understand the informal fallacies, you'll be able to sniff them out and utilize sound logic to discredit them.

Meet the Fallacies

Fallacies of Relevance

Fallacies of relevance have premises that do not “bear upon” the truth of the conclusions. In other words, they introduce an irrelevancy into the argument.

Ad Fontem Arguments

(Arguments against the Source): The Latin phrase ad fontem is literally translated as “to or from the fountain.” Ad fontem arguments are a subgroup of the fallacies of relevance, and they consist of arguments that focus on discrediting the source of the argument instead of analyzing the argument itself.

Ad Hominem
Abusive
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Ad Hominem
Circumstantial
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Tu Quoque
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Genetic Fallacy
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Appeal to Emotion

All fallacies appeal to our emotions in some form, but these kinds of fallacies do so in particularly irrelevant and obvious ways. Appeal to Emotion arguments are a subgroup of the fallacies of relevance and consist of arguments that focus on emotional manipulation rather than the issue at hand.

Appeal to Fear
Argumentum ad Baculum
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Appeal to Pity
Argumentum ad Misericordiam
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Mob Appeal
Argumentum ad Populum
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Snob Appeal
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The Wrong or False Expert
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Appeal to Tradition
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Appeal to Novelty
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Red Herrings

Red Herring arguments are a subgroup of the fallacies of relevance and include types of proofs that don’t attack the source or play on our emotions but nevertheless introduce points that are irrelevant to the issue under consideration.

Appeal to Ignorance
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Irrelevant Goals or Functions
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Irrelevant Thesis
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The Straw Man Fallacy
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Fallacies of Presumption

Fallacies that make unwarranted assumptions about either the data or the nature of a reasonable argument.

Fallacies of Presupposition

Fallacies of Presupposition are a subcategory of Fallacies of Presumption. They are derived from the verb “pre-suppose” and are the hidden, predetermined ideas or assumptions that an individual brings to an argument. A presupposition is an assumption that is hidden and that we unknowingly bring with us before we ever encounter any evidence (some might call these our biases).

Begging the Question
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Circular Reasoning
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Loaded Question
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Loaded Definition
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Loaded Label
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Bifurcation (False Dilemma)
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Fallacy of Moderation
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Is-Ought Fallacy
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Division
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Composition
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Fallacies of Induction

Fallacies of Induction are a subcategory of Fallacies of Presumption. These fallacies make unnecessary (or unwarranted) assumptions about empirical data or they fail to use proper inductive reasoning from that data. These fallacies are often hidden behind seemingly concrete facts and data.

Hasty Generalization (Converse Accident)
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Sweeping Generalization (Accident)
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False Analogy
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False Cause
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Post Hoc Ergo Propter Hoc
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Partial Cause
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Confusing Necessary and Sufficient Conditions
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Confusing Cause and and Effect
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Neglect of a Common Cause
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Fake Precision
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Fallacies of Clarity

Arguments that fail because they contain words, phrases, or syntax that distort or cloud their meanings.

Equivocation
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Distinction without a Difference
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