Appeal to Ignorance Fallacy | Definition & Examples

Reasoning updated on  March 5, 2024 4 min read

The appeal to ignorance fallacy occurs when a claim is considered true or false based solely on the absence of definitive proof of the contrary.

This logical fallacy is an attempt to sidestep the burden of proof by suggesting that the absence of preexisting counter-evidence is sufficient to prove the speaker’s claim.

Appeal to ignorance example
A celebrity defendant is acquitted of a crime, but the public disagrees with the verdict. A commentator defends the celebrity: “The prosecution couldn’t prove guilt beyond a reasonable doubt, so it’s been definitively proven that this person is innocent. Anyone who still questions the verdict is being unreasonable.”

This reasoning is an example of the appeal to ignorance fallacy because it wrongly suggests that the prosecution’s failure to definitively prove guilt implies the defendant’s innocence. In reality, the absence of irrefutable evidence can result in an acquittal, but it does not prove with certainty that the accused did not commit the crime.

Appeals to ignorance can be found in a variety of contexts, including law, marketing, and politics. This faulty line of reasoning can also be seen in discussions of paranormal activity and conspiracy theories.

What is the appeal to ignorance fallacy?

The appeal to ignorance fallacy involves assuming that a claim is true or false simply because the opposite has not been proven. This error is also known as the argument from ignorance fallacy and by its Latin name, argumentum ad ignorantiam.

The appeal to ignorance fallacy is flawed in part because it overlooks the possibility of future discoveries. It also disregards the fact that proving negative claims with certainty (e.g., proving that fairies have never existed anywhere in the universe) can sometimes be extremely difficult, if not impossible.

This fallacy is an informal logical fallacy, meaning that it pertains to an error in the content of the argument rather than its form.

The burden of proof fallacy is quite similar to the appeal to ignorance, and the two terms are sometimes used interchangeably. However, there is a key difference:

  • Appeal to ignorance fallacy: Assumes a claim is true because it has not yet been proven false
  • Burden of proof fallacy: Explicitly shifts the responsibility onto others to disprove the claim

Examples of the appeal to ignorance fallacy

Examples of the appeal to ignorance fallacy can be found in a wide variety of contexts, from claims about supernatural phenomena to debates on topics such as science and health.

Appeal to ignorance example in health
“There’s no proof that this new, unregulated supplement is harmful, so it must be safe.”

This argument employs the appeal to ignorance fallacy by mistaking the lack of irrefutable evidence of a supplement’s harmfulness, in the absence of rigorous testing, for evidence that it is safe. The lack of evidence that a substance is harmful might be due to a lack of research or long-term data, so it should not be mistaken for a guarantee of safety.

The appeal to ignorance fallacy can also be found in media, particularly in reports on scientific topics.

Appeal to ignorance example in media
In an opinion article critiquing the concept of so-called “superfoods,” a columnist cites an inconclusive scientific study as proof that blueberries don’t play any role in cancer prevention: “A recent study found no evidence to support the idea that blueberries helped prevent cancer in participants. This is clear proof that blueberries do not help prevent cancer, yet their reputation as a superfood persists.”

This argument is an example of the appeal to ignorance fallacy because the columnist incorrectly interprets an inconclusive study as definitive proof that blueberries have no value in preventing cancer. The writer assumes that the absence of evidence confirming blueberries’ benefits is the same as evidence of their ineffectiveness.

Why is the appeal to ignorance fallacy a problem?

The appeal to ignorance fallacy presents several problems:

  • Encourages false certainty: It involves interpreting a lack of evidence as definitive proof of a contrary claim.
  • Stifles inquiry: It discourages further investigation that could reveal new evidence.
  • Influences decisions: It can lead to policies or opinions that are based on incomplete information.
  • Creates false dichotomies: It simplifies complex issues into binary choices, implying that if a claim hasn’t been proven to be true, the opposite must be true.
  • Exploits biases: It persuades by appealing to cognitive biases, or common irrational thought patterns, rather than using evidence-based reasoning.

How can you respond to the appeal to ignorance fallacy?

To respond to the appeal to ignorance fallacy, consider the following strategies:

  • Explain the error: Point out the mistake of assuming that a mere lack of evidence for a claim proves that the opposite is true.
  • Acknowledge nuance: Remember that the truth might lie somewhere between, or outside, the two polar opposite possibilities presented.
  • Request legitimate evidence: Ask for direct evidence supporting the claim rather than accepting a lack of evidence to the contrary.
Do you want to know more about common mistakes, commonly confused words, or other language topics? Check out some of our other language articles full of examples and quizzes.

Common mistakes

Commonly confused words


Whoa or woah

Advisor vs adviser


Theirs or their's

Accept vs except


Ours or our's

Affect vs effect

Verbal irony

Forty or fourty

Among vs between


Sence or sense

Anymore vs any more


What are the two forms of the appeal to ignorance fallacy?

The appeal to ignorance fallacy can take two forms:

  • Arguing that a claim is true because it has not been proven false (e.g., “Ghosts are real because science has never disproved their existence.”)
  • Arguing that a claim is false because it has not been proven true (e.g., “We’ve found no clear evidence of life on other planets, so that proves we’re alone in the universe.”)

Both forms of the fallacy make the same essential error, misconstruing the absence of contrary evidence as definitive proof.

What is an example of an appeal to ignorance fallacy in real life?

The lack of definitive proof that cryptids, such as Bigfoot, do not exist is sometimes presented as evidence that they do exist. This line of argumentation is an example of the appeal to ignorance fallacy that one might encounter in everyday life.

What does absence of evidence mean?

The appeal to ignorance fallacy is often countered with the maxim “Absence of evidence is not evidence of absence.” A lack of evidence may merely reflect the current limitations of our knowledge; it does not necessarily mean that evidence will never be discovered.


Magedah Shabo

Magedah is an author, editor, and educator who has empowered thousands of students to become better writers.

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