Logical Fallacies A logical fallacy is an element

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Logical Fallacies • A logical fallacy is an element of an argument that is

Logical Fallacies • A logical fallacy is an element of an argument that is flawed • If spotted one can essentially render an entire line of reasoning invalid.

Usage • Fallacies in Society • However, fallacies are very common and can be

Usage • Fallacies in Society • However, fallacies are very common and can be persuasive • You can find dozens of fallacies in newspapers, advertisements, and other sources.

Purpose • Shows that the opposition • Purpose of Recognizing has made an error

Purpose • Shows that the opposition • Purpose of Recognizing has made an error in Fallacies in argumentation reasoning • Shows you understand the opposition's argument • Is a way of removing an argument rather than just weakening it

Types of Fallacies • Ad Hominem – argument directed at the person. • Attacking

Types of Fallacies • Ad Hominem – argument directed at the person. • Attacking the character or motives of a person, rather than the idea itself. • The most obvious example of this fallacy is when one debater maligns the character of another

Types of Fallacies • False Dilemma / Bifurcation Fallacy • When someone is asked

Types of Fallacies • False Dilemma / Bifurcation Fallacy • When someone is asked to choose between two options when there is at least one other option available • Complex questions are subtle forms of false dilemma. Questions such as “Are you going to admit that you’re wrong? ”

Types of Fallacies • Straw man • Giving the extreme version of somebody's argument,

Types of Fallacies • Straw man • Giving the extreme version of somebody's argument, rather than the actual argument they've made. • Often involves putting words into somebody's mouth by saying they've made arguments they haven't actually made • http: //www. youtube. com/ watch? v=y. Je. HF 5 PHrd. Q

Types of Fallacies • Straw man, Continued • A straw man can entice an

Types of Fallacies • Straw man, Continued • A straw man can entice an opponent into defending a silly argument • This strategy only works if the straw man is a subtle exaggeration and not too different from the arguments your opponent has made

Types of Fallacies • False Premise • In this fallacy, the conclusion is invalidated

Types of Fallacies • False Premise • In this fallacy, the conclusion is invalidated by an incorrect or assumptive premise. • Since the premise is not correct, the conclusion may also be incorrect

Types of Fallacies • Ad Antiquitatem – the argument to tradition Some traditions, like

Types of Fallacies • Ad Antiquitatem – the argument to tradition Some traditions, like the Chinese tradition of binding feet, are clear examples of why the tradition argument can be weak • The argument that something is acceptable because "it's always been done that way. “ • Ad Antiquitatem is easily refuted by simply pointing it out, and in general it should be avoided.

Types of Fallacies • Non Sequitur – It does not follow • A disconnection

Types of Fallacies • Non Sequitur – It does not follow • A disconnection between the premise and the conclusion. • Stating, as a conclusion, something that does not follow from the premises. • Non Sequitur is often stated a connection without explanation

Types of Fallacies • Non Sequitur, Continued • • The best time to point

Types of Fallacies • Non Sequitur, Continued • • The best time to point out a non sequitur is when your opposition is trying to construct a chain of causation (A leads to B leads to C, etc. ) without justifying each step in the chain. For each step in the chain they fail to justify, point out the non sequitur, so that it is obvious the chain of causation is weak

Types of Fallacies • Argumentum ad ignorantiam (argument to ignorance). • • This is

Types of Fallacies • Argumentum ad ignorantiam (argument to ignorance). • • This is the fallacy of assuming something is true simply because it hasn't been proven false. But failing to prove the global warming theory false is not the same as proving it true. For example, someone might argue that global warming is certainly occurring because nobody has demonstrated conclusively that it is not.

Types of Fallacies • Begging the Question • A form of logical fallacy in

Types of Fallacies • Begging the Question • A form of logical fallacy in which an argument is assumed to be true without evidence other than the argument itself. • HINT: Don’t use “begs the question” to mean “raises the question. ”

Types of Fallacies • Slippery Slope • • The argument that taking one action

Types of Fallacies • Slippery Slope • • The argument that taking one action will lead to a series of other policies or actions also being taken A slippery slope occurs when there is no causal connection between the advocated policy and the consequent policies.

Types of Fallacies • Argumentum ad nauseam • This is the fallacy of trying

Types of Fallacies • Argumentum ad nauseam • This is the fallacy of trying to prove something by saying it – argument to the point of disgust again and again. • Repetition alone doesn’t substitute for real arguments.

Types of Fallacies • Argumentum ad numerum (argument or appeal to numbers). • This

Types of Fallacies • Argumentum ad numerum (argument or appeal to numbers). • This fallacy is the attempt to prove something by showing how many people think that it's true. • Whether supported by numbers or not supported, that doesn't necessarily make it true or right. • This fallacy is very similar to argumentum ad populum, the appeal to the people or to popularity.

Logical Fallacy • Bandwagon Appeal- Everyone is doing it so you should too!

Logical Fallacy • Bandwagon Appeal- Everyone is doing it so you should too!

Logical Fallacy • Circular reasoning- a logical fallacy in which the reason-er begins with

Logical Fallacy • Circular reasoning- a logical fallacy in which the reason-er begins with what they are trying to end with. (See begging the question) "A is true because B is true; B is true because A is true. "

Logical Fallacy • False Causality -occurs when one cites to sequential events as evidence

Logical Fallacy • False Causality -occurs when one cites to sequential events as evidence that the first caused the second

Logical Fallacy • Overgeneralization-Claims which use words like all, never, most, and seldom not

Logical Fallacy • Overgeneralization-Claims which use words like all, never, most, and seldom not as figures of speech but as ways of avoiding assessing or questioning the likeliness of an event which is part of the claim. Ex. Hondas never get better gas mileage than Volkswagens.

Logical Fallacy • Oversimplification-whenever the series of actual causes for an event are either

Logical Fallacy • Oversimplification-whenever the series of actual causes for an event are either reduced or multiplied to the point where there is no longer a genuine, causal connection between the alleged causes and the actual effect. • Self-Contradiction-lines of argumentation that undermine their own argument by contradicting the original premise

Logical Fallacy • Red Herring-statements intended to divert attention from the issue at hand

Logical Fallacy • Red Herring-statements intended to divert attention from the issue at hand to another, usually less significant, issue.