Logical Fallacy Reference Guide

Understanding Logical Fallacies
A comprehensive guide to identifying and countering common reasoning errors

Logical fallacies are errors in reasoning that undermine the logic of an argument. They often appear persuasive and can be difficult to spot, but they rely on faulty logic rather than sound evidence. This guide helps you identify 18 common fallacies, understand why they're problematic, and learn how to counter them effectively.

18
Fallacies Documented
7
High Severity
8
Medium Severity
3
Low Severity
Straw Man
Relevance
high severity
Misrepresenting someone's argument to make it easier to attack

The straw man fallacy occurs when someone distorts, exaggerates, or misrepresents an opponent's position to make it easier to refute. Instead of addressing the actual argument, they attack a weaker version they've constructed.

Common in:
Political debates
Legal arguments
Social media discussions
Contract negotiations
Ad Hominem
Relevance
high severity
Attacking the person rather than their argument

Ad hominem attacks target the character, motive, or attributes of the person making an argument rather than addressing the substance of the argument itself. This diverts attention from the actual issue being discussed.

Common in:
Political campaigns
Court proceedings
Academic debates
Online discussions
Slippery Slope
Causation
medium severity
Assuming one action will inevitably lead to a chain of events without evidence

The slippery slope fallacy assumes that a relatively small first step will inevitably lead to a chain of related events culminating in a significant (usually negative) effect, without providing evidence for this causal chain.

Common in:
Policy debates
Legal arguments
Business decisions
Ethical discussions
False Dichotomy
Presumption
high severity
Presenting only two options when more exist

Also called 'false dilemma' or 'black-and-white thinking', this fallacy presents a situation as having only two possible options when in reality there are more alternatives available.

Common in:
Political rhetoric
Marketing
Legal arguments
Negotiations
Appeal to Authority
Relevance
low severity
Using authority as evidence without proper justification

While expert opinion can be valuable, this fallacy occurs when authority is used as the sole or primary evidence, especially when the authority is not qualified in the relevant field or when the claim requires additional evidence.

Common in:
Advertising
Expert testimony
Policy arguments
Scientific discussions
Hasty Generalization
Presumption
high severity
Making broad claims without sufficient evidence

This fallacy involves drawing a general conclusion from a small or unrepresentative sample. It's the basis of stereotyping and prejudice, where limited experiences are extrapolated to entire groups.

Common in:
Stereotyping
Market research
Legal testimony
Social commentary
Post Hoc Ergo Propter Hoc
Causation
medium severity
Assuming causation from correlation or sequence

Latin for 'after this, therefore because of this', this fallacy assumes that because one event followed another, the first must have caused the second. It confuses correlation with causation.

Common in:
Scientific claims
Policy evaluation
Medical reasoning
Historical analysis
Bandwagon
Relevance
medium severity
Arguing something is true because many believe it

The bandwagon fallacy appeals to popularity or common practice as evidence for truth or correctness. Just because many people believe something doesn't make it true.

Common in:
Marketing
Social pressure
Political campaigns
Trend following
Red Herring
Relevance
medium severity
Introducing irrelevant information to distract from the main argument

A red herring is a distraction technique that introduces irrelevant information to divert attention from the actual issue being discussed. It's often used to avoid addressing difficult questions.

Common in:
Political debates
Cross-examination
Negotiations
Public relations
Circular Reasoning
Presumption
high severity
Using the conclusion as evidence for itself

Also called 'begging the question', circular reasoning occurs when the conclusion of an argument is assumed in one of its premises. The argument goes in a circle without providing independent support.

Common in:
Philosophical arguments
Religious debates
Legal reasoning
Definitional disputes
Appeal to Emotion
Relevance
medium severity
Using emotional manipulation instead of valid reasoning

This fallacy attempts to win an argument by manipulating emotions (fear, pity, anger, etc.) rather than presenting logical evidence and reasoning. While emotions are important, they shouldn't replace sound argumentation.

Common in:
Political speeches
Charity appeals
Legal closing arguments
Advertising
False Equivalence
Ambiguity
high severity
Incorrectly claiming two things are equivalent when they're not

This fallacy draws a comparison between two things that are not truly comparable, suggesting they are equivalent in some important way when they differ significantly.

Common in:
Political debates
Moral arguments
Legal comparisons
Media analysis
Appeal to Tradition
Relevance
low severity
Arguing something is correct because it's traditional

This fallacy assumes that because something has been done a certain way for a long time, it must be the correct or best way. It resists change based solely on tradition.

Common in:
Organizational resistance
Cultural debates
Legal precedent
Business practices
Appeal to Novelty
Relevance
low severity
Arguing something is better simply because it's new

The opposite of appeal to tradition, this fallacy assumes that newer is automatically better. It values innovation without considering whether the new thing is actually an improvement.

Common in:
Technology marketing
Business trends
Academic theories
Product advertising
Tu Quoque
Relevance
medium severity
Dismissing criticism by pointing out hypocrisy

Latin for 'you too', this fallacy attempts to discredit an argument by pointing out that the person making it doesn't follow their own advice. However, hypocrisy doesn't make the argument wrong.

Common in:
Personal disputes
Political debates
Parenting
Workplace conflicts
Loaded Question
Presumption
medium severity
Asking a question that contains an unproven assumption

A loaded question contains a controversial or unjustified assumption, making it impossible to answer without appearing to accept that assumption. The classic example is 'Have you stopped beating your wife?'

Common in:
Cross-examination
Journalism
Political interviews
Debates
No True Scotsman
Ambiguity
medium severity
Dismissing counterexamples by redefining terms

This fallacy occurs when someone makes a universal claim, is presented with a counterexample, and then modifies the claim to exclude the counterexample by redefining the terms.

Common in:
Identity debates
Professional standards
Ideological purity tests
Group membership
Begging the Question
Presumption
high severity
Assuming the conclusion in the premise

Similar to circular reasoning, begging the question occurs when an argument's premise assumes the truth of the conclusion instead of supporting it. The argument doesn't actually prove anything new.

Common in:
Philosophical arguments
Legal reasoning
Scientific explanations
Definitional debates