Skip to main content

Logical fallacies 

A useful set of 'refutational tools' whose usage is mainly seen in random internet arguments but can also equally be applied in the IRL realm too, such as against your wife or your boss. The former scenario is where people often abuse logical fallacies to the point of committing a fallacy fallacy, so be wise and use them sparingly and only as a supplement to your argument.

Also related to non sequitur.
1) Jim called out his boss by using logical fallacies to poke holes in his ridiculous decisions.
2) Tommy used logical fallacies to his advantage in order to expose the inconsistencies in his girlfriend's reasoning with regards to how he should spend his money.
Urban Dictionary Merch
Your favorite words on things you can wear, drink from, read, or give to a friend.
The Urban Dictionary Store sells gifts you’ll have to explain.

Hard Problem of Logical Fallacies

The frustrating reality that identifying a logical fallacy in someone's argument does not automatically prove their conclusion wrong, nor does it validate your own. Fallacies are flaws in reasoning, not truth detectors. The "hard problem" is the temptation to use fallacy labels (e.g., "that's just an ad hominem!") as a rhetorical knockout punch, ending the discussion while providing zero substantive counter-argument. This reduces critical thinking to a game of fallacy bingo, where the goal is to spot errors rather than collaboratively pursue truth. A conclusion reached via fallacious reasoning can still be accidentally true, and a logically pristine argument can lead to a false conclusion if its premises are wrong.
Example: Person A: "We should fix the bridge. The engineer who designed it is a known liar!" Person B: "Ad hominem fallacy! Invalid argument, the bridge is fine." B has correctly spotted a fallacy (attacking the person, not the bridge's condition), but has done nothing to assess the actual safety of the bridge. The hard problem: Winning the logical battle doesn't win the factual war. The bridge might still be crumbling, but the conversation is now dead, replaced by a smug scorecard of who used logic correctly. Hard Problem of Logical Fallacies.

Law of Spectral Logical Fallacies

The principle that logical fallacies exist on a spectrum between absolute and relative, with infinite gradations and multiple dimensions. Under this law, a claim isn't simply fallacious or not fallacious—it's fallacious to some degree, in some contexts, under some interpretations, for some purposes. The law of spectral fallacies recognizes that what counts as a fallacy depends on standards of reasoning that themselves vary across domains, cultures, and purposes. An argument that's clearly fallacious in a philosophy seminar might be perfectly acceptable in a political speech; a move that's invalid in formal logic might be persuasive in everyday conversation. The spectral view allows for nuanced evaluation rather than binary dismissal.
Law of Spectral Logical Fallacies Example: "She analyzed his argument using spectral fallacies, mapping it across dimensions: formal logical fallacies (present but weak), rhetorical effectiveness (high), contextual appropriateness (depends on audience), cultural reasoning norms (acceptable in his tradition). The spectral coordinates explained why some listeners were convinced and others were appalled. She stopped calling it simply fallacious and started understanding its complex effects."

Law of Absolute and Relative Logical Fallacies

The principle that fallacies operate in two modes: absolute fallacies (errors that are fallacious in all logical systems, by any reasonable standard) and relative fallacies (errors that are fallacious in some systems but may be acceptable in others). The law acknowledges that some errors are universally wrong—affirming the consequent is a mistake in any logic that cares about validity. Other errors are system-dependent—what counts as a fallacy in formal logic may be perfectly acceptable in rhetorical argument. The law of absolute and relative fallacies reconciles these by recognizing that fallaciousness has both universal and context-dependent dimensions.
Law of Absolute and Relative Logical Fallacies Example: "He accused her of ad hominem, claiming it was an absolute fallacy. She pointed out that in political debate, attacking character is sometimes relevant and not always fallacious. The law of absolute and relative fallacies said: in formal logic, absolutely fallacious; in political rhetoric, context-dependent. Both were right, which is why fallacies are complicated."

Hard Problem of Logical Fallacy Fallacies

Also known as the Fallacy Fallacy Problem: The self-defeating mistake of dismissing an argument solely because it contains a logical fallacy. This is the meta-error where calling out a fallacy becomes a fallacy itself (argument from fallacy). It assumes that if the reasoning is flawed, the conclusion must be false. This creates a logical trap where any critique can be infinitely regressed: "You used a fallacy to point out my fallacy, so your critique is invalid!" It turns discourse into a hall of mirrors where the act of policing logic destroys the possibility of communication.
Example: Alex: "Climate change is real because 99% of scientists say so, and you're a oil shill for denying it!" (This commits an appeal to authority and an ad hominem). Blake: "Ha! You used two fallacies! Therefore, climate change isn't real!" Blake has committed the fallacy fallacy. Alex's conclusion (climate change is real) is supported by massive evidence independent of their flawed reasoning. Dismissing the conclusion because of the poor argument is a critical failure. The hard problem: Spotting fallacies is easy; knowing what to do with that information without committing a greater error is the real intellectual work. Hard Problem of Logical Fallacy Fallacies.
More from Urban Dictionary
British slang for a scientist or technical expert, esp . when the speaker is not certain of the expert’s specific field of study. Not necessarily derogatory, but typically used by persons without a technical background. In the US, the equivalent would be “egghead”, “squint”, or “geek.”

Origin of the word is unknown. Started sometime in World War 2. Given the typical evolution of British slang, could easily have started because what these experts did was confusing or “baffling” to the common person.
According to the boffins downstairs, the murderer used a serrated blade.
Boffin by Agnon February 11, 2023
Word of the Day on October 3, 2026

Pee Calculus

When you have to pee in a movie but don’t want to miss anything, and must do the following mental equation: will the amount I have to pee cause enough discomfort to diminish my attention capacity for the remainder of the movie to an extent which is greater than the amount of the movie I would miss by making a mad dash to the restroom.
I saw Satantango last night, wonderful film but by the 5th hour I had to start doing pee calculus.
Pee Calculus by anorlondo October 1, 2026
Word of the Day on October 2, 2026
Literally "dirty" pronounced with a West Indian accent. Can also have a positive connotation, for example Sean Paul's album title "Dutty Rock".
"The girl is pretty but she corrupt and dutty!"

or, in a positive usage:

"Booya! That freestyle was dutty!"
Dutty by J Hall April 3, 2003
Word of the Day on October 1, 2026
korean word for madam, older woman
Ajumma wait a moment
Ajumma by aintnotinbutnice July 5, 2009
Word of the Day on September 30, 2026

Slop Grenade

When someone uses AI to generate a large document, slide deck, or piece of code/software and tosses it over the fence for you to deal with.
Chad: Hey Brent I sent you the new backend API change to review, it’s only 100 files changed.

Brent: he just tossed me a slop grenade
Slop Grenade by Joe Squid September 28, 2026
Word of the Day on September 29, 2026
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).
After we broke up, he was floxi to me.
floxi by Dr. Geek May 13, 2009
Word of the Day on September 28, 2026
Load more