FALLACIES AND TRAPS

You commit logical fallacies every day. So do I. So does every politician, every scientist, every philosopher who ever lived. The question isn't whether you're immune to bad reasoning—nobody is. The question is whether you can recognize flawed arguments when you encounter them, including your own.

This chapter offers no shortcut to perfect logic. What it offers is a map of the territory where arguments go wrong. Some of these errors are obvious once you see them; others are subtle enough to fool careful thinkers for years. Understanding fallacies won't make you infallible, but it will make you dangerous—to bad arguments, and to anyone hoping to sneak one past you.

A word of caution before we begin. Knowing the names of fallacies can become its own intellectual trap. There's a certain satisfaction in shouting "ad hominem!" or "straw man!" at your opponent, but naming a fallacy isn't the same as demonstrating it. And sometimes what looks like a fallacy is actually a reasonable argument in context. The goal here is understanding, not ammunition for lazy dismissal.

THE TWO FAMILIES OF FALLACIES

Fallacies come in two broad types, and the distinction matters. Formal fallacies are structural errors—the argument's form is broken regardless of content. Informal fallacies are content errors—the argument's structure might be fine, but something has gone wrong in how the premises relate to the conclusion. Most fallacies you'll encounter in the wild are informal. Formal fallacies show up mainly in philosophy classes and computer science.

Here's a formal fallacy: "All dogs are mammals. My cat is a mammal. Therefore, my cat is a dog." The problem isn't in the premises—both are true. The problem is in the structure. Just because all dogs belong to the mammal category doesn't mean everything in that category is a dog. This is called "affirming the consequent," and it produces invalid conclusions no matter what content you plug in. The form itself is broken.

Informal fallacies are trickier because the structure often looks fine. "We should legalize marijuana because it's natural" has a clear claim and premise. But the premise (natural) doesn't actually support the conclusion (should be legal). Poison ivy is natural too. Earthquakes are natural. Smallpox is natural. The argument relies on an unstated assumption—that natural things are good—and that assumption is false. This is the "appeal to nature" fallacy. The structure works, but the content fails.

Understanding this distinction helps you respond appropriately. When someone commits a formal fallacy, you can dismiss the conclusion regardless of the premises—the argument simply doesn't work. When someone commits an informal fallacy, you need to explain why the premises don't support the conclusion. The response requires more nuance because the failure is in the reasoning, not the structure.

THE GREATEST HITS

Some fallacies appear so frequently that they've become household names—at least in households that care about argument. These are the ones you'll encounter most often, and they're worth knowing cold.

The ad hominem fallacy attacks the person instead of the argument. "You can't trust his economic analysis—he's never held a real job." The speaker's employment history might be interesting context, but it doesn't actually address whether the analysis is correct. A trust-fund philosopher might be right about economics; a seasoned banker might be wrong. Arguments stand or fall on their own merits.

But be careful here. Sometimes personal characteristics are relevant. If a pharmaceutical company funds a study of its own drug, that's worth knowing. The study might still be correct, but the financial interest is legitimate context for skepticism. The fallacy occurs when we use personal attacks to dismiss an argument without engaging it. "He's biased, so I don't have to consider his evidence" is fallacious. "He's biased, so I should examine his evidence especially carefully" is just good sense.

The straw man fallacy misrepresents an opponent's position, then attacks the misrepresentation. "My opponent wants to defund the police, leaving our streets lawless!" But the opponent's actual position might be reallocating some police funding to mental health services—a far cry from abolishing law enforcement. The straw man is easier to attack than the real argument, which is precisely why dishonest debaters construct them.

Straw men are insidious because they can happen accidentally. We all have a tendency to hear arguments through the filter of our expectations. If you already think environmentalists are extremists, you might genuinely hear a moderate carbon tax proposal as "they want to destroy our economy." Combating straw men requires disciplined attention to what your opponent actually said—and the intellectual honesty to represent it fairly, even when you disagree. We'll explore this in depth in Chapter 15 on steelmanning.

The false dilemma (also called "false dichotomy" or "either/or fallacy") presents only two options when more exist. "You're either with us or against us." "You either support this policy or you want children to die." "It's either socialism or a free market." Reality rarely offers only two choices. The middle ground, the third way, the "both/and" option—these possibilities get erased by the false dilemma, leaving you forced to choose between extremes.

The appeal to authority substitutes credentials for evidence. "Einstein believed in God, so God must exist." Einstein's genius in physics doesn't make him an expert on theology. The appeal to authority becomes fallacious when the authority isn't actually authoritative in the relevant domain, or when authority is used to shut down inquiry rather than inform it. Citing a climate scientist on climate change is reasonable; citing that same scientist on economic policy isn't.

The slippery slope argues that one step will inevitably lead to a chain of increasingly dire consequences. "If we allow assisted suicide for terminally ill patients, soon we'll be euthanizing anyone who becomes inconvenient." The fallacy lies in assuming the chain of consequences without demonstrating why each step necessarily follows. Some slopes are genuinely slippery—some policy changes really do create momentum for further changes. But you have to show the mechanism, not just assert it.

Scroll through any social media comments section and you'll see the greatest hits on repeat. Someone critiques a policy; responses attack their profile picture. Someone proposes a nuanced position; it gets exaggerated into an extreme and mocked. Someone raises a concern; they're told to choose between two impossible alternatives. The platforms didn't invent these moves. Aristotle catalogued them. But the speed of digital exchange strips away the social friction that once made fallacies costly. In a Athenian assembly, strawmanning someone's position in front of six thousand citizens who heard what they actually said carried real reputational risk. Online, you can misrepresent someone to an audience who never saw their original words. The fallacies are ancient. The scale is new.

FALLACIES OF RELEVANCE

These fallacies involve premises that don't connect to the conclusion—irrelevant material masquerading as support. The appeal to emotion substitutes feeling for evidence. "How can you support building a prison near our neighborhood? Think of the children!" The fear doesn't address whether the prison poses actual risk. Emotion can supplement reasoning (as Chapter 7 explored), but it becomes fallacious when it replaces it.

The appeal to tradition argues that because something has been done a certain way, it should continue. But past practice doesn't justify present policy. The appeal to popularity (ad populum) argues that because many believe something, it must be true. "Millions can't be wrong!" Actually, millions can be wrong—popular beliefs have included the flatness of the Earth and the rightness of slavery.

The red herring introduces a tangential topic to distract. "Why worry about my spending when there are people starving?" The existence of worse problems doesn't make your problem irrelevant—the speaker has simply changed the subject.

FALLACIES OF PRESUMPTION

These fallacies presume something that should be proven. Begging the question (circular reasoning) assumes the conclusion in the premises. "God exists because the Bible says so, and the Bible is true because it's the word of God." Each claim depends on the other, proving nothing.

The loaded question presumes something controversial as established fact. "Have you stopped beating your wife?" Either answer implies you were beating her. The proper response: reject the premise. Hasty generalization draws broad conclusions from insufficient evidence—a few encounters inflated into universal claims. This fallacy is the engine behind stereotypes.

False cause (post hoc ergo propter hoc) assumes that because one thing followed another, the first caused the second. "The economy improved after the new president took office, so his policies worked." Correlation isn't causation—two events can occur in sequence for countless reasons.

THE FALLACY FALLACY

The fallacy fallacy assumes that because an argument contains a fallacy, its conclusion must be wrong. But that doesn't follow. "Smoking is bad because my grandfather smoked and died young" is a hasty generalization—one case can't prove a general claim. But smoking is bad for you, and we have mountains of evidence to prove it. The speaker's argument was weak, but their conclusion was correct.

Fallacy-hunting can become a substitute for thinking. Naming a fallacy feels like winning, even when you haven't addressed the underlying issue. The proper response to a weak argument is to explain why it's weak and to address whether the conclusion might still be true on other grounds. Sometimes your opponent's reasoning is flawed but their instinct is sound. The productive move is to help them articulate a stronger argument.

THE GRAY AREAS

What looks like a fallacy in one context might be reasonable in another. If a convicted fraudster testifies as an expert witness, questioning their credibility isn't ad hominem—their history of deception is directly relevant. The fallacy occurs when character attacks replace engagement with arguments, not when character is genuinely relevant.

If 97% of climate scientists agree human activity is warming the planet, citing that consensus is an appeal to authority—but a legitimate one. The scientists are genuine experts, and the consensus reflects careful review of evidence. We can't personally verify every scientific claim; reasonable deference to expertise is a practical necessity.

The key is evaluating arguments on their merits rather than dismissing them by category. The question isn't "Is this an appeal to authority?" but "Is this a legitimate appeal to authority?" Fallacy names are diagnostic tools, not verdicts. They help you identify where an argument might be weak, not where it certainly fails.

FALLACIES IN THE WILD

Real-world fallacies hide in sophisticated language. In the 1988 presidential debate, Dukakis gave a policy-focused response about the death penalty; Bush's campaign painted him as emotionally detached. The actual position (opposing state execution on principle) was never engaged—a textbook straw man. Recognizing this requires asking: "What did the person actually claim, and is that what's being attacked?"

"You're either tough on crime or soft on crime" dominated American politics for decades, erasing alternatives: community policing, mental health intervention, restorative justice. When someone presents only two options, ask: "What's the third? The fourth?" The false dilemma works by narrowing your imagination before you can consider alternatives.

When climate scientist Michael Mann presented temperature data, critics called him a "fraud" and questioned his funding—but didn't engage the data. When you see personal attacks, check whether the underlying argument is being addressed. If not, someone is hoping you'll confuse character assassination with refutation.

COUNTERING WITHOUT YELLING "FALLACY!"

Shouting "That's a straw man!" rarely works—it sounds defensive and starts a meta-debate about logic instead of the actual issue. Identifying the fallacy is only the first step. Dissolving it gracefully is the real skill.

The pattern: don't diagnose the fallacy, dissolve it. Reframe so the fallacy can't continue. Your opponent doesn't need to know the Latin name for their error—they just need to find themselves unable to persist in it. And often, when you respond gracefully rather than accusatorially, they'll recognize the error themselves. That's a better outcome than winning an argument about whether they committed a logical sin.

FALLACY RECOGNITION IN REAL TIME

In a SuperDebate round, a meeting, or a dinner table argument, you don't have time to consult a textbook. You need to recognize fallacies by their trigger phrases—the words that signal bad reasoning is coming. Here's a pattern-recognition guide.

Example Exchanges

Here's how fallacies sound in real conversation—and how to respond without naming them.

Ad Hominem in Action:

• Them: "Why should we listen to you about education reform? You don't have kids."
• You: "I understand the concern about perspective. But let's look at the policy itself—does it address the problems teachers are reporting? Whether or not I have kids doesn't change the data from classroom studies."
• Why this works: Acknowledge their concern, redirect to the argument's merits.

Straw Man in Action:

• Them: "So you think we should just let criminals roam free?"
• You: "No, I said we should fund mental health intervention alongside policing. That's different from releasing criminals. Can we discuss the specific policy I proposed?"
• Why this works: Correct the misrepresentation calmly, restate your actual position, invite engagement.

False Dilemma in Action:

• Them: "You're either with us or against us."
• You: "I think there's a third option—I can support some of your goals while disagreeing with your methods. Most things aren't binary."
• Why this works: Name the third option, refuse the forced choice.

Slippery Slope in Action:

• Them: "If we allow assisted suicide, soon we'll be euthanizing anyone who's inconvenient."
• You: "Can you help me understand the mechanism? How does one step lead to the other? Other countries have had these policies for decades—what happened there?"
• Why this works: Ask for the causal chain, introduce real-world evidence.

Appeal to Authority in Action:

• Them: "Dr. Smith says this treatment works, and he's a famous doctor."
• You: "What's his specialty? Is it relevant to this treatment? And what do other experts in that specific field say?"
• Why this works: Probe whether the authority is actually relevant, seek broader consensus.

Red Herring in Action:

• Them: "Why worry about carbon emissions when there's poverty to solve?"
• You: "Both matter. But right now we're discussing climate policy. Can we finish this before moving to poverty?"
• Why this works: Acknowledge the other issue's importance, return to the original topic.

Post Hoc in Action:

• Them: "Crime dropped after we increased police funding. Clearly, more police means less crime."
• You: "That's interesting timing. But what else changed in that period? Demographics, economy, other policies? Correlation needs more support to become causation."
• Why this works: Point to confounding variables, ask for causal mechanism.

In SuperDebate's cross-examination phase, these quick redirects are essential. You have 3 minutes—no time for a philosophy lecture. The goal is to expose the weakness and move on. For detailed cross-examination tactics, see the Live Response Guide.

FALLACIES AS STRATEGY: FOUR BAD-FAITH PATTERNS

Some people don't commit fallacies by accident. They deploy them strategically, turning argument into combat. The fallacies we catalogued above—ad hominem, straw man, red herring, false dilemma—become weapons in the hands of bad-faith arguers. Recognizing the underlying pattern helps you respond to the strategy, not just the individual fallacy.

The Dodger never engages directly. You raise climate policy; they attack your carbon footprint. You cite evidence; they question your credentials. You make a point; they make a different point. Each response sounds like engagement—it's still vaguely about the topic—but it never addresses what you actually said. The dodger survives by keeping the conversation in perpetual motion. Pin them down. "That's a different question. Let's finish with this one first." Return to your point as many times as necessary. Patience defeats evasion.

The Twister transforms what you said into something you didn't. "I support criminal justice reform." "So you want to empty the prisons?" They know that's not what you said. They're betting you'll either accept the caricature or exhaust yourself correcting it. The twister wins by making you defend positions you never held. Correct once, calmly, then redirect. "That's not my position—I said reform, not abolition. Now, can you engage with what I actually said?" Don't let them control the framing.

The Wrangler fights over everything except the point. Every solution you propose has fatal flaws—flaws they'd forgive in their own positions. They demand impossible certainty from your evidence while treating their assumptions as self-evident. Nothing you offer is ever enough. The wrangler wins by exhaustion, not argument. Force symmetry. "What would convince you? And does your position meet that same standard?" Make them play by their own rules.

The Liar overwhelms with volume. Fifteen claims in two minutes—each dubious, none sourced. By the time you've fact-checked the first, they've moved on to the fourteenth. This technique (sometimes called the "Gish Gallop") exploits a structural asymmetry: making false claims takes seconds; refuting them takes minutes. The liar wins by flooding the zone. Don't chase every claim. Pick one or two central ones. "You've made many claims. Let's verify this one first." When you demonstrate that one claim is false, the pattern becomes visible.

Not everyone who displays these patterns is beyond reach. Sometimes people deflect or distort because they feel attacked. Sometimes they criticize without offering alternatives because they genuinely haven't thought their position through. The patterns describe behaviors, not identities. Calling out the behavior—gently, without accusation—often brings people back to good faith. "I feel like we keep talking past each other. Can we slow down and make sure we're addressing the same question?" The goal is productive conversation, not winning against a villain.

DEPLOYING YOUR KNOWLEDGE

Knowing about fallacies serves three purposes: improving your own arguments, evaluating others', and occasionally calling out particularly egregious reasoning. The first two matter most.

When constructing arguments, use fallacy knowledge as a checklist. Am I attacking the person or the argument? Does my evidence actually support my conclusion? This self-scrutiny catches errors before your opponent does. When evaluating others' arguments, fallacy awareness helps locate weakness—but often it's better to ask probing questions than announce diagnoses. "How do those two steps connect?" does more work than "That's a non sequitur."

The goal isn't winning arguments through superior technique. It's thinking more clearly—holding beliefs that are actually supported by evidence. When you find yourself reaching for a fallacious argument, that's a signal: your position might be weaker than you thought. The discomfort of that realization is the feeling of getting smarter.