Logical Fallacies ERWC What is a logical fallacy

Logical Fallacies ERWC

What is a logical fallacy? • Definition: statements that might sound reasonable or superficially true but are actually flawed or dishonest

Why are logical fallacies used if they’re wrong? • They can work if the audience isn’t knowledgeable • Unintentional in younger, less experienced thinking/writing

Types of Fallacies • Fallacies of Relevance: Evidence that is used is irrelevant to the claim • Fallacies of Accuracy: Evidence is intentionally or unintentionally wrong • Fallacies of Insufficiency: Not enough evidence is provided • Others

Slippery Slope • Definition: This is a conclusion based on the idea that if A happens, then B, C…X, Y, Z will happen, too; therefore, A shouldn’t happen. • Effect: shifts attention to extreme hypotheticals instead of the issue at hand • Appeal to pathos (usually fear)

Slippery Slope Examples • We have to stop the tuition increase! The next thing you know, they'll be charging $40, 000 a semester!" • "The US shouldn't get involved militarily in other countries. Once the government sends in a few troops, it will then send in thousands to die. " • If we ban Hummers because they are bad for the environment eventually the government will ban all cars, so we should not ban Hummers.

Ad hominem • Definition: This is an attack on a person’s character or personal traits rather than his/her opinions or arguments. • Effect: By attacking the person, it casts doubt on their character, thus undermining someone’s case w/o actually having to argue the issue. • Fallacy of Relevance

Ad hominem Example: Green Peace’s strategies aren’t effective because they are all dirty, lazy hippies.

Red Herring • Definition: A remark that is irrelevant or has only surface-level relevance, usually emotionally-loaded. • Effect: mislead and distract an audience from the actual facts. • Fallacy of Relevance

Red Herring Example • The level of mercury in seafood may be unsafe, but what will fishers do to support their families? • Mike: It is morally wrong to cheat on your spouse, why on earth would you have done that? Ken: But what is morality exactly? Mike: It’s a code of conduct shared by cultures. Ken: But who creates this code? . . .

Straw Man • Definition: When a speaker chooses a poor or oversimplified version of an argument to make it easier to attack • This is done by exaggerating, misrepresenting, misquoting, leaving out key information, or completely fabricating an argument • Effect: Presents your own position as reasonable in comparison (dishonest) • Fallacy of Accuracy

Straw Man Example • People who don’t support the proposed state minimum wage increase hate the poor. • Bill and Jill are arguing about cleaning out their closets: Jill: "We should clean out the closets. They are getting a bit messy. " Bill: "Why, we just went through those closets last year. Do we have to clean them out everyday? " Jill: "I never said anything about cleaning them out every day. You just want too keep all your junk

Either/Or Fallacy (AKA False Dilemma) • Definition: Two extreme choices are presented as the only possible choices when in fact more possibilities exist • Effect: appearance of a logical argument • Fallacy of Accuracy

Either/Or Fallacy Examples • “Either we agree to higher taxes, or our grandchildren will be mired in debt” (Ausfes et al. 103). • We can either stop using cars or destroy the earth.

Anecdotal Fallacy • Definition: Using personal experience as evidence instead of logos • Effect: It can be enough to the right audience as convincing evidence • Students, be careful about this fallacy being in your writing (inexperience, lack of enough info) • Fallacy of Insufficiency

Anecdotal Fallacy Example • Smoking isn’t harmful. My grandfather smoked a pack a day and lived until 97. • Global warming? Yeah, right! It was a record low in my town today.

Hasty Generalization • Definition: This is a conclusion based on insufficient evidence. In other words, you are rushing to a conclusion before you have all the relevant facts. • Effect: If you have a conclusion that sounds strong, the untrained audience will be satisfied with this • Fallacy of Insufficiency

Fallacies: Part 2

Faulty analogy • Often used to appeal to pathos • Example: an expensive product is pictured with a famous person and a connection is made between the product’s purpose or qualities and the famous person’s talent(s). • Fallacy of Relevance

Fallacies of accuracy Evidence is intentionally or unintentionally WRONG

Either/or fallacy (aka false dilemma) • Two extreme choices are presented as the only possible choices • EXAMPLES • “Either we agree to hire taxes, or our grandchildren will be mired in debt” (Ausfes et al. 103). • We can either stop using cars or destroy the earth. • In this example, the two choices are presented as the only options, yet the author ignores a range of choices in between such as developing cleaner technology, carsharing systems for necessities and emergencies, or better community planning to discourage daily driving.

Fallacies of insufficiency NOT ENOUGH evidence is provided

Hasty Generalization This is a conclusion based on insufficient or biased evidence. In other words, you are rushing to a conclusion before you have all the relevant facts.

Examples of Hasty Generalization • I met a Lebanese woman today who was incredibly smart and kind; therefore, all Lebanese women must be smart and kind. • The weather was really hot yesterday; therefore, that must be evidence of global warming. • The weather was really cold yesterday; therefore, global warming must not exist.

Circular reasoning or Begging the Question • This restates the argument rather than actually proving it.

Circular Reasoning Examples • Whatever is less dense than water will float, because such objects won't sink in water • If such actions were not illegal, then they would not be prohibited by the law.

Other common logical fallacies

Slippery Slope This is a conclusion based on the premise that if A happens, then eventually through a series of small steps, through B, C, . . . , X, Y, Z will happen, too, basically equating A and Z. So, if we don't want Z to occur, A must not be allowed to occur either.

Examples of the Slippery Slope Fallacy • We have to stop the tuition increase! The next thing you know, they'll be charging $40, 000 a semester!" • "The US shouldn't get involved militarily in other countries. Once the government sends in a few troops, it will then send in thousands to die. " • If we ban Hummers because they are bad for the environment eventually the government will ban all cars, so we should not ban Hummers.

Post Hoc (Ergo propter hoc) • This is a conclusion that assumes that if 'A' occurred after 'B' then 'B' must have caused 'A. '

Post Hoc Examples • The rooster crowed, and then the sun came up. Therefore, the rooster caused the sun to come up. • I took a pill and then felt better. Therefore, the pill cured my illness.

Syllogism is a rhetorical device that starts an argument with a reference to something general and from this it draws conclusions about something more specific. Syllogism is a three-part set of statements; a major statement or premise, a minor statement or premise and a conclusion that is deduced. Example: All crows are black and the bird in my cage is black. So, the bird in my cage is a crow. This is a false argument as it implies a conclusion “all black birds are crows, ” which is incorrect.

Bandwagon (ad populum) • “Everybody’s doing it, so it must be a good thing to do” (Aufses et al. 111). • This is an emotional appeal that speaks to positive (such as patriotism, religion, democracy) or negative (such as terrorism or fascism) concepts rather than the real issue at hand. • Statistics can sometimes be manipulated to give a bandwagon appeal the appearance of logos. Example: • If you were a true American you would support the rights of people to choose whatever vehicle they want. • In this example, the author equates being a "true American, " a concept that people want to be associated with, particularly in a time of war, with allowing people to buy any vehicle they want even though there is no inherent connection between the two.

Appeal to false authority • “Someone who has no expertise to speak on an issue is cited as an authority” (Ausfes et al. 110). • This often happens with celebrities endorsing products. • Verify ethos to avoid this fallacy.

Key Fallacies to Review • Red Herring and Ad-hominem • • Faulty Analogy Straw Man Either/Or Fallacy Hasty Generalization • • Slippery Slope Post Hoc Syllogism Bandwagon (Ad Populum) • Appeal to False Authority