Wendy Lewis only

Poor Reasoning and Fallacies Cheat Sheet

Appeal to the People (Bandwagon) - Claiming that something is true just because many people

believe it is. Example: Everybody buys this product, so it must be the best one.

Faulty Appeal to Authority - Using research without naming the source, such as, "Many researchers

say..." or answering questions one is not qualified to answer. Example: I asked my dentist if he thought

this mole was cancerous. He said “No” so I do not need to get it checked out.

Proof by Lack of Evidence (Burden of Proof) - Asserting something is true just because there is no

evidence it's false. Example: UFO’s exist because no one has ever been able to prove they don’t.

Innuendo – Making a claim without actually making the claim. Example:

Non Sequitur - It doesn't follow logically. Samantha lives in a large building; therefore she must have a

large home.

Fake Dilemma (Black and White) – Presenting two alternative states as the only possibilities, when in

fact there are more. Example: "You are either for the U.S. or against the U.S." doesn't allow for neutral

countries.

Naturalistic Fallacy (Appeal to Nature) - Making the argument because something is “natural”, it is

therefore valid, good or the way it’s supposed to be. Example: This product uses all natural ingredients

therefore it’s the only one on the market you should buy.

Circular Reasoning (Begging the Question) – Using the statement to prove the conclusion and the

conclusion to prove the statement. Example: The word of Zorbo the Great is flawless and perfect. We know this

because it says so in The Great and Infallible Book of Zorbo's Best and Most Truest Things that are Definitely True and

Should Not Ever Be Questioned.

Overgeneralization – Asserting something is an entire class of things when it may not be true for all

members of the class. Example: Beth is a Psychology student and shy is shy, therefore all psychology

students are shy.

False Analogy (Slippery Slope) – Making a false or misleading analogy. Example: Colin Closet asserts

that if we allow same-sex couples to marry, then the next thing we know we'll be allowing people to marry their

parents, their cars and even monkeys.

Jumping to Conclusions – Drawing conclusions with little evidence. Example: My son is crying, you

must have taken his toy.

Being Unrealistic – Using only information in an unrealistic manner. Example: The candidates just all

graduated from college… therefore they should not take a job for less than 6 figures.

Verbal Fallacies (Ambiguity) – Accenting, omitting, or misusing certain words to influence or mislead

the reader or listener. Example: After the team lost, Susan became mad. (upset, angry, insane, happy…

who knows)

Using only information that supports your argument (Texas Sharpshooter) - Example: Research

says a glass of wine a day is good for my heart. So drinking is good for my heart!

Source: Jesse Richardson, Andy Smith and Som Meaden, www.fallacydetective.com, and HU260 Strategies for Decision Making - W6

Lecture "Critical Thinking"