The Writing Desk · Craft

How to Find Logical Fallacies in Any Argument

7 min readUpdated September 2026

Spotting a logical fallacy is a skill, not a talent — and like any skill, it comes down to a method you can repeat. Whether you're stress-testing someone else's op-ed or your own draft, the same few moves surface almost every broken argument. Here's the process.

1. Separate the claim from the support

Every argument is a claim plus the reasons given for it. Before you can judge the reasoning, you have to see it clearly. Read the passage once and write down, in your own words: What is the author asking me to accept? And what are they offering as a reason to accept it? Fallacies hide in the gap between those two things.

2. Test whether the conclusion actually follows

Reduce the argument to its bones — a syllogism of two premises and a conclusion. If the premises were true, would the conclusion have to be true? When the answer is no, you've found the flaw: the conclusion doesn't follow from the premises. Many syllogistic fallacies are exactly this — a broken link between what's given and what's claimed.

3. Scan for the usual patterns

Most everyday fallacies fall into a handful of recognizable shapes. Once you know them by name, you see them everywhere:

Is the author answering the real opposing view, or a straw man of it?
Are they attacking the argument, or the person making it — an ad hominem?
Are you being offered only two options when more exist — a false dilemma?
Is an irrelevant point pulling attention away from the issue — a red herring?
Does the case rest on a name or title rather than evidence — an appeal to authority?

A fallacy is just a shortcut where an argument should be. Name the shortcut, and the argument falls apart on its own.

Let the Writing Lab do a first pass

Paste any argument — yours or someone else's — and the Writing Lab flags each fallacy in the text and links it to a full explanation.

Check an argument →

4. Watch for the emotional shortcut

When a passage makes you feel something strongly — fear, outrage, belonging — pause. Emotion isn't a fallacy, but it's often used in place of one. Ask whether the feeling is doing the work a reason should. That's the mark of an appeal to emotion, and it's one of the most common ways a weak argument slips past a reader's guard.

5. Turn the method on your own writing

The hard part is that fallacies are far easier to see in arguments you disagree with. In your own draft, you already believe the conclusion, so the gaps feel invisible. The fix is to read your argument as an opponent would: hunt for the weakest link, the claim that outruns its evidence, the objection you quietly skipped. If you can't find anything wrong, you probably haven't looked hard enough — or you haven't looked from the outside.

Build the habit

Finding fallacies gets faster the more you name them. Start with the shortlist of common fallacies, learn to recognize each on sight, and run the five steps above on anything you're about to publish. Before long, the weak spots announce themselves.