Logical Fallacies

LogFall

A practical logical-fallacies reference with clear explanations, usable examples, and teaching tools.

Fallacy profile

Bare assertion fallacy

Occurs when a contested claim is simply asserted, often confidently, without the evidence needed to justify it.

EvidentialTactical

Definition

Occurs when a contested claim is simply asserted, often confidently, without the evidence needed to justify it.

Illustrative example

The jobs report was obviously manipulated. Everyone knows that.

Teaching gauges

These 0-100 gauges are teaching aids for comparing fallacies. They are editorial classroom estimates, not measured statistics.

Near-constant

95

Common in today's rhetoric

Shows up constantly in current politics, media, and online argument.

Easy to catch

70

Easy to spot

Often easy to catch with a little attention.

Very easy to slip into

70

Easy to innocently commit

A frequent unintentional slip in ordinary reasoning.

Foundational

25

Difficulty

Usually approachable without much prior logic background.

Middle school+Scientific reasoning

Reference

Family

Evidential/Methodological Fallacy

The mistake lies in how evidence is gathered, weighed, interpreted, or treated as sufficient.

Aliases

ipse-dixitism, proof by assertion

Quick check

What evidence is missing, selected, or overstretched here?

Why it misleads

A fuller explanation of how the fallacy works and why it can look persuasive.

Confidence, volume, and repetition can make a bare assertion sound weighty, but they do not do the evidential work. When the core support is missing, the proper question is still: What is the evidence?

That's like saying...

Instead of leading with the label, this analogy answers the shape of the reasoning move directly so the mistake is easier to see in plain language.

Fallacious claim

The jobs report was obviously manipulated. Everyone knows that.

That's like saying...

That's like slamming a stamp on a blank file and calling the case closed. Confidence of assertion is replacing actual support.

Caveat

This label is easy to overuse. The point here is not to call every weak argument by this name, but to reserve it for the exact misstep it describes.

Common misapplication

Do not use this label simply because the evidence is incomplete. It applies when the argument claims more support than the evidence has actually earned.

Use the label only when...

Use this label only when a contested claim is simply asserted, often confidently, without the evidence needed to justify it. If the real problem is that support for a claim is borrowed from a source that is fabricated, misquoted, unqualified, anonymous in the wrong way, or otherwise not what it is presented to be, the better label is False attribution.

Often confused with

These near neighbors are easy to mix up, so use the comparison to see the exact difference.

Comparison

False attribution

Why people mix them up: Both often look like evidential and tactical mistakes at first glance.

Exact difference: Bare assertion fallacy happens when a contested claim is simply asserted, often confidently, without the evidence needed to justify it. False attribution happens when support for a claim is borrowed from a source that is fabricated, misquoted, unqualified, anonymous in the wrong way, or otherwise not what it is presented to be.

Quick split: What evidence is missing, selected, or overstretched here? Then compare it with What evidence is missing, selected, or overstretched here?

Comparison

Cherry picking

Why people mix them up: Both often look like tactical and evidential mistakes at first glance.

Exact difference: Bare assertion fallacy happens when a contested claim is simply asserted, often confidently, without the evidence needed to justify it. Cherry picking happens when someone selects only the evidence that supports a conclusion and ignores a wider body of evidence that weakens, qualifies, or reverses it.

Quick split: What evidence is missing, selected, or overstretched here? Then compare it with Is the argument still addressing the original issue, or has the conversation been steered away?

Practice And Repair

Extra teaching tools that show why the fallacy is persuasive, what to look for, and how to correct it.

Why it matters

Why this mistake matters

Bare assertion fallacy threatens rationality because a contested claim is simply asserted, often confidently, without the evidence needed to justify it.

Main reasoning problem

A contested claim is simply asserted, often confidently, without the evidence needed to justify it.

Why this kind of mistake matters

It overstates, understates, cherry-picks, or misallocates the force of evidence.

Check yourself

The assessment area now uses mixed 10-question sets, so the fallacy is not announced in the title before the quiz begins.

What the assessment does

You will work through a mixed set of fallacy-identification questions. Focused links from a fallacy page will quietly include this fallacy among nearby look-alikes without announcing the answer in the page title.

Questions to ask

Use these category-based prompts to audit similar arguments.

Prompt 1

What evidence is missing, selected, or overstretched here?

Prompt 2

Is the argument still addressing the original issue, or has the conversation been steered away?

Case studies

Each case study explains why the example fits the fallacy and links back to its source whenever source information is available.

Researchers say an AI-powered transcription tool used in hospitals invents things no one ever said

AP's reporting on Whisper hallucinating in hospital transcripts is a sharp case of a polished output being treated as if accuracy followed from confidence and fluency. It also shows why one plausible-seeming example is not enough to certify a tool as reliable in high-stakes settings. The fallacy here is Bare assertion fallacy: a contested claim is simply asserted, often confidently, without the evidence needed to justify it. That matters here because confidence, volume, and repetition can make a bare assertion sound weighty, but they do not do the evidential work. A better analysis would remember that when the core support is missing, the proper question is still: What is the evidence?

Associated Press · 2024-10-26

Top Haitian official denounces false claim, repeated by Trump, that immigrants are eating pets

AP's September 26, 2024 report on Haiti's transitional council president condemning the Springfield pet-eating rumor shows how quickly a sensational falsehood can travel from fringe posts to a presidential debate to the United Nations. The case is vivid enough to illustrate both emotional manipulation and the costs of repeating an unverified claim because it 'sounds like what the other side would do.' The fallacy here is Bare assertion fallacy: a contested claim is simply asserted, often confidently, without the evidence needed to justify it. That matters here because confidence, volume, and repetition can make a bare assertion sound weighty, but they do not do the evidential work. A better analysis would remember that when the core support is missing, the proper question is still: What is the evidence?

Associated Press · 2024-09-26

Authorities rebut claims that Haitian immigrants are eating cats, waterfowl in Ohio town

PolitiFact's September 9, 2024 Springfield fact check is a neat example of a rumor built out of anonymous posts, recycled images, and suggestive repetition rather than verifiable support. It shows how easily a story can feel established before it has actually been checked. The fallacy here is Bare assertion fallacy: a contested claim is simply asserted, often confidently, without the evidence needed to justify it. That matters here because confidence, volume, and repetition can make a bare assertion sound weighty, but they do not do the evidential work. A better analysis would remember that when the core support is missing, the proper question is still: What is the evidence?

PolitiFact · 2024-09-09

How an unsubstantiated, anonymous affidavit about the ABC presidential debate was amplified online

PolitiFact's September 20, 2024 reconstruction of the fake ABC whistleblower affidavit is especially valuable because it shows how public figures shared the claim while conceding they did not know whether it was true. That is a live, well-documented case of conjecture and amplification outrunning authentication. The fallacy here is Bare assertion fallacy: a contested claim is simply asserted, often confidently, without the evidence needed to justify it. That matters here because confidence, volume, and repetition can make a bare assertion sound weighty, but they do not do the evidential work. A better analysis would remember that when the core support is missing, the proper question is still: What is the evidence?

PolitiFact · 2024-09-20

Biden tells Trump to 'get a life, man' and stop storm misinformation

AP's October 10, 2024 report on hurricane-response misinformation is a clean example of how disaster politics invites fear-based claims that spread faster than verification. The article is especially useful for showing how emotionally convenient numbers and slogans can be detached from what agencies actually said. The fallacy here is Bare assertion fallacy: a contested claim is simply asserted, often confidently, without the evidence needed to justify it. That matters here because confidence, volume, and repetition can make a bare assertion sound weighty, but they do not do the evidential work. A better analysis would remember that when the core support is missing, the proper question is still: What is the evidence?

Associated Press · 2024-10-10

Related fallacies

Nearby entries chosen by shared categories and family resemblance.