# Fallacies of Logic

## 27 terms

### Fallacy

A misleading or unsound argument; flaws in reasoning that lead to illogical statements (Ex: All nerds wear glasses and pocket protectors)

### Premise

The basis, stated or assumed, on which reasoning proceeds; the foundation, like a thesis statement or a hypothesis (Ex: Obama's only real accomplishment has been his change in foreign policy)

### Syllogism

Conclusion derived from two premises; one term is excluded from the conclusion (Ex: My phone is gone, the person next to me is a thief, thus the person next to me stole my phone / If a=b, and b=c, then a=c)

### Deductive Reasoning

Reasoning from the general to the particular (cause to effect); if premises are true, conclusion must be true (Ex: Geometric proof- theories to the problem you're working on)

### Inductive Reasoning

Reasoning from detailed facts to general principles; begin with a specific instance and draw generalizations (Ex: Because my ink pen contains black ink, all ink is black)

### Cogent

Appealing to the intellect or powers of reasoning (Ex: any strong argument)

### Specious

An argument that appears good at first view but is really a fallacy (Ex: Animal rights activists saying we must give all beings equal consideration and treatment)

### Hasty Generalization

Making an assumption from insufficient data; generalizing from insufficient evidence (Ex: stereotyping)

### False Analogy

Incorrect connection between two things that aren't similar; a comparison in which the differences outweigh the similarities, or the similarities are irrelevant to the claim (Ex: stupid as a rock)

### Circular Argument

An assertion merely restated in slightly different terms; uses circular reasoning to make a conclusion on material that has already been assumed (Ex: Boxing is dangerous because it is not safe)

### Non Sequitur

Conclusion does not follow the premises; statement does not follow what logically precedes it (Ex: She is a good speaker, so she should be mayor)

### Post Hoc Ergo Propter Hoc

Results when someone assumes that sequence alone proves something; because something happens in a sequence of events, one thing caused another (Ex: The four leaf clover gave me an A on the exam)

Two premises are used that cannot simultaneously be true; two ideas cannot coexist because the contradict each other (Ex: Never say never)

### Red Herring

Sidetracks an issue by bringing up a totally unrelated issue; avoiding topic in question by bringing up a different idea (Ex: Used to distract dogs from a scent)

### Appeal to the Person

Ad hominem; attacks the appearance, personal habits, or character of the person involved instead of dealing with the merits of the issue at hand; irrelevant details about the person you are arguing against (Ex: He can't be our president, his shoes are red!)

### Bandwagon

Implies that something is right because everyone is doing it; cause that garners followers by its mass appeal or strength (Ex: Saints win the Superbowl, so everyone becomes a fan)

### False Authority

Using an incredible, suspicious, or biased source to defend a conclusion; attempts to transfer prestige from one area to another (Ex: Tennis star promoting Gatorade / It happened to me, it will happen to you)

### Card-Stacking

Ignores evidence on the other side of a question; person arguing only selects the facts that will build the best/worst possible case; propaganda technique to manipulate the audience's view by biasing them to the issue; one-sided (Ex: The diet plan that does not work for everyone)

### Either/Or Fallacy

Also, false dilemma; offers only two alternatives when more exist; attempt to force audience to choose between two options (Ex. Republican or Democrat? or Communism or Anarchy?)

### Out of Context

Separates an idea or fact from the material surrounding it, thus distorting it (Ex: Movie critic calls music fantastic, and moviemakers say "Critics call this movie fantastic!")

### Appeal to Ignorance

Assumes that an argument is valid simply because there is no evidence on the other side of the issue; speaker concludes something just because there's nothing against it (Ex: The world will end in 2012 because we have no evidence to the contrary.)

### Slippery Slope

Uses one weakness in a position to assume that the whole is doomed to failure; claims that a particular weakness will make the whole argument fall apart (Ex: We have to win in Vietnam, or the entire Southeast will become Communist.)

### Ambiguity

Expressions that are not clear because they have more than one meaning; may be taken either way by the reader; statement that is unclear, can have two meanings (Ex: I can't tell you how much I love your cooking)

### Equivocation

used in two ore more ways within a single argument; expression used in multiple ways (Ex: The president played an important role in negotiations[....] The president only played a role.)

### Tu Quoque

An unsound argument that justifies itself by pointing out the unsoundness of the opposing argument; a retort accusing an accuser of a similar behavior (Ex: "You got a B in English, and that is unacceptable." "Didn't you get a B in English as well?")

### Ignoratio Elenchi

Arguing for something different from the question asked; avoiding the question asked by arguing about something different (Ex: Soldier asked to describe his military service responds with "Defending your country is important.")

### Straw Man

Opponent's argument is overstated or misrepresented; made to be easily refuted; the actual issue remains untouched; used to showcase one side of the argument by giving the appearance of a weak opposing argument (Ex: Pro-Choicers say Pro-Lifers want women to be raped and get pregnant)