Logical Fallacies Study Guide

The Slippery Slope

A fallacy that assumes that taking a first step will lead to subsequent steps that cannot be prevented. This fallacy, instead of focusing on the prime issue, shifts to the extreme hypotheticals that may never exist. A form of Appeal to Emotion fallacy because it provokes fear.

Loaded question

A question that is biased because it contains a built-in assumption. Particularly effective in disrupting rational debates with their inflammatory nature. Recipient of this fallacy is compelled to defend themselves.

Bandwagon

Appealing to popularity or the fact that many people do something as an attempted form of validation. This fallacy has no bearing on validity.

Appeal to authority

Appeals to an authority to support a position/idea. Should not be used to dismiss the claims of experts. Appeals to authority are not valid arguments, but nor is it reasonable to disregard the claims of experts who have a demonstrated depth of knowledge unless one has a similar level of understanding and/or access to empirical evidence.

Genetic Fallacy

Arguments that state that an idea should be discounted simply because of its source or origin. This fallacy avoids the argument by shifting focus onto something's or someone's origins. Similar to Ad Hominem.

Composition/division

Assuming that what's true about one part of something has to be applied to all or other parts of it. Often when something is true for the part it does also apply to the whole, or vice versa, but the crucial difference is whether there exists good evidence to show that this is the case.

Ad Hominem

Attacking the person's character instead of the present argument. This fallacy can take the form of casting doubt on a person's argument or personal attributes to undermine their argument.

Personal Incredulity

Because you found something difficult to understand, or are unaware of how it works, you made out like it's probably not true. Complex subjects require some understanding before you are able to make a judgement. This fallacy is the replacement of that particular understanding.

The Gambler's Fallacy

Believing that 'runs' occur to statistically independent phenomena such as roulette wheel spins.

Strawman

False representation of an argument to make it easier to attack. Undermines rational debate.

The Texas sharpshooter

Jumping to the conclusion that a cluster in some data must be the result of a cause. This 'false cause' fallacy is coined after a marksman shooting randomly at barns and then painting bullseye targets around the spot where the most bullet holes appear, making it appear as if he's a really good shot.

Appeal to nature

Making the argument that because something is 'natural' it is therefore valid, justified, inevitable, good, or ideal. Many 'natural' things are also considered 'good', and this can bias our thinking; but naturalness itself doesn't make something good or bad.

No true Scotsman

Making what could be called an appeal to purity as a way to dismiss relevant criticisms or flaws of an argument. In this form of faulty reasoning one's belief is rendered unfalsifiable because no matter how compelling the evidence is, one simply shifts the goalposts so that it wouldn't apply to a supposedly 'true' example.

Define Logical Fallacy

Mistakes/flaws within reasoning

Middle ground

Saying that a compromise, or middle point, between two extremes is the truth. Much of the time the truth does indeed lie between two extreme points, but this can bias our thinking: sometimes a thing is simply untrue and a compromise of it is also untrue.

False cause

The assumption that a real or perceived relationship means that one is the cause of the other. The confusion of correlation for causation.

The Fallacy Fallacy

The assumption that, because a claim has been poorly argued, or that a fallacy has been made, the entire claim must be false. It is very possible to argue with a false claim yet do so with logical coherency, just as it is equally possible to make a true claim and justify it with fallacies and poor arguments.

Appeal to Emotion

The attempt to manipulate an emotional response in a place of a valid/compelling argument. Appeals to Emotion include fear, hatred, pride, pity, and more. This tactic is common due to the fact everyone is subject to emotion.

Ambiguity

The multiple meanings, either intentional or unintentional, of a word/phrase. Politicians are often guilty of using ambiguity to mislead and will later point to how they were technically not outright lying if they come under scrutiny.

Begging the question

The situation that results when a writer or speaker constructs an argument on an assumption that the audience does not accept. This logically incoherent argument often arises in situations where people have an assumption that is very ingrained, and therefore taken in their minds as a given.

Burden of proof

This fallacy lies not with the relies solely on someone else to disapprove. The inability, or disinclination, to disprove a claim does not render that claim valid, nor give it any credence whatsoever. A very important note would be that we must assign value to any claim with valid evidence.

Tu Quoque

Turning your back on an argument an answering a criticism with a criticism. The literal translation of u Quoque is "You too", and is commonly employed to take the heat off someone having to defend themselves or their presented argument.

Special Pleading

Using double standards to excuse an individual or group. Rather than try to change one's mind through further understanding, many find it easier to cling to old beliefs. Long story short, people find excuses rather than information.

Anecdotal

Using personal experience or an isolated example instead of a valid argument especially to dismiss statistics. It's often much easier for people to believe someone's testimony as opposed to understanding complex data and variation across a continuum.

Black-or-white

Where two alternative states are presented as the only possibilities, when in fact more possibilities exist. Also known as the false dilemma, this insidious tactic has the appearance of forming a logical argument, but under closer scrutiny it becomes evident that there are more possibilities than the either/or choice that is presented.