Pointing at a pattern is faster than writing a paragraph about it. That's the whole pitch.
When someone in a thread makes an argument that fits one of the patterns on this site, the temptation is to type out a long reply explaining what's wrong with it. By the time you've written it, three more people have joined the thread and it's moved on. Most of the time, your effortful paragraph is wasted.
fallacy.is is built for the other approach: name the move with a short URL, let the page do the explaining, and trust that the person on the other end (or anyone reading along) can take the explanation in without you needing to repeat it. The pages are written to help. They're not written to humiliate.
This is a short guide to using the site well.
The basic move
Every entry on fallacy.is has a short URL. Drop the URL into the reply. That's the whole thing.
| Pattern | Use it like this |
|---|---|
| Canonical slug | Worth a read on this: fallacy.is/straw-man |
| Two-letter alias | fallacy.is/sm — that's not quite what was said |
| Bare URL | fallacy.is/whataboutism |
Most platforms (Reddit, Twitter, Discord, Slack, Hacker News, comment sections) auto-link bare URLs. On the few that don't, wrap it in your platform's link syntax. The link unfurls into a card with the fallacy's name and definition on the platforms that support it.
What the page actually says
If you're linking someone an entry, it helps to know what they'll read. Every entry has the same shape:
- In plain terms — the fallacy explained in everyday language
- Why it's fallacious — the structural reason the reasoning struggles
- Canonical example — a realistic case
- Counter-example (not a fallacy) — a case that looks similar but isn't, to help readers distinguish the line
- How to fix it — practical guidance for someone who might have made the argument, plus brief notes for the responder
The "How to fix it" section is written for the speaker, not the citer. That's deliberate. People who land on a fallacy page after being linked there are usually the person whose argument got flagged. The most useful thing the page can do is help them think about the argument better, not make them feel cornered.
When linking is helpful
It works when:
- The pattern is named and well-known. Straw man and ad hominem are widely recognized. Most readers will understand what you mean without clicking.
- Bystanders are reading. You're unlikely to change the mind of the person you're replying to. You might help everyone else watching understand the question better. A short link does that work efficiently.
- The fallacy is clear on one read. If you have to explain why something is a fallacy after linking it, the link isn't doing the work. Pick a clearer example or skip the citation.
When to skip it
A short link is a tool, not a reflex. Skip it when:
- The pattern is subtle. Many real arguments hover near the line between a fallacy and a legitimate move. Slippery slope arguments can be valid when the mechanism is shown. Appeals to authority can be legitimate when the authority is qualified and the argument cites their reasoning. If the call is close, posting a link without context looks lazy or hostile.
- You're trying to win. Linking a fallacy doesn't make you right. It makes the original argument less right. Those aren't the same thing.
- The fallacy is on your side too. Linking ad hominem right after delivering one yourself is a tu quoque invitation in waiting.
- It's a private conversation. With friends, family, coworkers, paste-the-link is colder than the moment usually deserves. Talk it through.
A practical pattern
If you only remember one thing: link + restate the original argument without the fallacy attached.
Them: "Anyone who supports raising the minimum wage has never run a business."
You: "fallacy.is/ad-hominem might be useful here. The argument is about the policy, not about who's making it. Is raising the minimum wage good or bad on the merits?"
The link does the labeling. Your sentence pulls the conversation back to the actual question. The tone matters too — "might be useful here" lands very differently than "lol look it up." The point isn't to mark a win. The point is to clarify what's being argued.
Picking the right entry
The most common mistake is grabbing the closest-named fallacy when a different one is the better fit. A few that get confused often:
- Whataboutism vs. tu quoque — whataboutism deflects to a side or group ("but the other party..."); tu quoque is personal ("but you did the same thing").
- Straw man vs. motte and bailey — straw man weakens your opponent's position; motte and bailey is when they swap their own strong claim for a weak one when challenged.
- Ad hominem vs. genetic fallacy — ad hominem attacks the person; genetic fallacy attacks the source (which might be an institution, a publication, or a funding body, not a person).
- Appeal to authority vs. bandwagon — authority is one credentialed name; bandwagon is "everyone agrees."
If you're not sure which fits, the full list groups everything by category and reading three definitions takes under a minute. A precise citation is more useful than a loud one.
What to do if someone links a fallacy at you
The mirror move. Sometimes you'll be on the receiving end. The graceful response is the same one you'd want them to make:
- Click the link. Read the entry. Don't assume it's a gotcha. Most of the time, the page is more reasonable than the citation made it sound.
- If the citation lands, say so. "Fair, that was a straw man. What I meant was..." This is rarely the loss it feels like. It's the cleanest move available.
- If the citation misses, say why. Every entry has a "Counter-example (not a fallacy)" section. Use it. "I read it. I don't think this applies because..." is a strong reply.
Defensive escalation after a fair citation is how threads turn into wars. Conceding small points and clarifying the actual claim is how threads stay useful.
One last thing
The short link is a tool for labeling arguments, not for replacing them. Use it to clarify what's being discussed. Use it sparingly enough that when it appears, it carries weight. Don't use it as a substitute for thinking, and don't use it as a substitute for being kind.
If something here was useful, the full list is one click away.