Teaching path
Start here
A foundational sequence for first-time readers and classrooms starting with the fallacies they are most likely to meet in ordinary discussion.
12 fallacies
Best for middle school through intro college.
Logical fallacies made clearer, more teachable, and easier to compare.
LogFall is a practical reference for spotting, naming, comparing, and correcting reasoning mistakes. Each entry combines a definition, a concrete example, case studies, a companion illustration, related fallacies, and a guided practice tool.
Teaching paths
Curated routes through the site for first-time readers, public-debate analysis, and high-confusion review sessions.
Teaching path
Most common in public debate
A classroom-ready path centered on the moves that appear constantly in campaigns, punditry, and online argument.
12 fallacies
Best for civics, debate, media literacy, and rhetoric courses.
Teaching path
Most often confused
A comparison path for near neighbors that students and readers regularly collapse into one another.
12 fallacies
Best for high school and college review sessions.
Browse the taxonomy
The taxonomy groups fallacies by the main kind of reasoning failure involved, which makes nearby mistakes easier to compare.
Formal
Breakdowns in deductive structure where the conclusion does not follow from the form.
13 entries
Mathematical
Missteps involving probability, statistics, scope, quantity, or numerical expectations.
11 entries
Causal
Faulty claims about what caused what, or what causal link has actually been shown.
10 entries
Linguistic
Confusion created by wording, ambiguity, framing, or unstable definitions.
15 entries
Conceptual
Errors caused by bad categories, weak distinctions, or distorted conceptual boundaries.
51 entries
Evidential
Arguments that overstate what the evidence shows, ignore what is missing, or misuse support.
56 entries
Perceptual
Mistakes rooted in appearances, impressions, or the way something seems at first glance.
3 entries
Perspectival
Errors caused by the wrong vantage point, historical standpoint, or interpretive frame.
13 entries
Epistemic
Failures in belief management, confidence calibration, or standards for responsible belief.
10 entries
Tactical
Debate maneuvers that distract, derail, pressure, or strategically reroute the exchange.
30 entries
Emotional
Arguments that make feeling do the evidential work reasoning should have done.
17 entries
Featured fallacies
A starter set of especially common reasoning errors that are useful for classrooms, debates, and self-audit.
Ad hominem
Occurs when someone treats an attack on a person's character, motives, class, or biography as if it were a refutation of that person's argument.
TacticalEmotional
Foundational
Middle school+
Appeal to authority
Occurs when someone treats an authority's endorsement as if it settled the issue, even when the authority is unqualified, the field is divided, or the claim still require...
EvidentialEmotional
Foundational
Middle school+
Base rate fallacy
Occurs when someone judges how likely a case is by focusing on vivid case-specific evidence while ignoring the underlying frequency of the thing in question.
Mathematical
Foundational
Middle school+
Begging the question
Occurs when an argument quietly assumes the very point it is supposed to prove, so the conclusion is built into the premises.
Formal
Foundational
Middle school+
Cherry picking
Occurs when someone selects only the evidence that supports a conclusion and ignores a wider body of evidence that weakens, qualifies, or reverses it.
TacticalEvidential
Foundational
Middle school+
Correlation is not causation
Occurs when someone treats a correlation, coincidence, or time pattern as if it already established that one factor caused the other.
Causal
Foundational
Middle school+
Equivocation
Occurs when a key word or phrase slides between different meanings inside the same argument, creating the illusion of support.
Linguistic
Foundational
Middle school+
False dilemma
Occurs when someone presents a limited set of options as if they were the only live possibilities, while reasonable alternatives are ignored or suppressed.
Conceptual
Foundational
Middle school+
Moving the goalpost
Occurs when evidence that was supposed to satisfy a stated standard is dismissed and a new, harder standard is introduced so the conclusion never has to be reconsidered.
TacticalEvidential
Foundational
Middle school+
No True Scotsman
Occurs when someone protects a generalization from counterexamples by redefining the group with an ad hoc 'real' or 'true' membership test.
ConceptualLinguistic
Foundational
Middle school+
Slippery slope
Occurs when someone claims that a relatively small first step will trigger a chain of worsening outcomes without showing why that chain is likely, stable, or hard to stop...
CausalConceptual
Foundational
Middle school+
Straw man argument
Occurs when someone replaces an opponent's actual position with a weaker, more extreme, or simplified version and then refutes that easier target.
Tactical
Foundational
Middle school+