Logical Fallacies

Logical Fallacies

“There’s a mighty big difference between good, sound reasons and reasons that sound good.” Burton Hills, cited in Laurence J. Peter’s Peter, Quotations: Ideas for Our Time (1977), p. 425

What is a logical fallacy? • A "fallacy" is a mistake, • and a "logical" fallacy is a mistake in reasoning.

What is a logical fallacy? • The text Everything’s An Argument clarifies that logical fallacies are not necessarily indicators of flawed logic, but rather are attempts to move and/or manipulate the audience:

“Certain types of argumentative moves are so controversial they have been traditionally classified as fallacies…. But you might find it more interesting to think of them as flashpoints or hotspots because they instantly raise questions about the ethics of argument—that is, whether a particular strategy of argument is fair, accurate, or principled.”

“Fallacies are arguments supposedly flawed by their very nature or structure; as such, you should avoid them in your own writing and challenge them in arguments you hear or read. That said, it’s important to appreciate that one person’s fallacy may well be another person’s stroke of genius (384–385).”

Fallacies are commonly categorized in these groups: • FALLACIES OF RELEVANCE • FALLACIES OF AMBIGUITY • COMPONENT FALLACIES • FALLACIES OF OMISSION

FALLACIES OF RELEVANCE: appeal to evidence or examples that are not relevant to the argument at hand.

FALLACIES OF RELEVANCE: • Appeal to Force (or the "Might-Makes-Right" Fallacy) • Personal Attack (Argumentum Ad Hominem, "Poisoning the Well") • Appeal to Authority • Appeal to Tradition • Appeal to Improper Authority • Appeal to Emotion

FALLACIES OF AMBIGUITY: These errors occur with ambiguous words or phrases, the meanings of which shift and change in the course of discussion. Such more or less subtle changes can render arguments fallacious.

FALLACIES OF AMBIGUITY • Equivocation • Amphiboly (from the Greek word "indeterminate • Composition • Division

COMPONENT FALLACIES • Component fallacies are errors in inductive and deductive reasoning. Deductive is where facts are determined by combining existing statements, while Inductive is where facts are determined by repeated observations

COMPONENT FALLACIES • Begging the Question • False Analogy • Circular Reasoning • Hasty Generalization • Missing the Point • False Cause • Straw Man Argument • Slippery Slope • False Dilemma - Either/Or

FALLACIES OF OMISSION • These errors occur because the logician leaves out necessary material in an argument or misdirects others from missing information.

FALLACIES OF OMISSION • Stacking the Deck or Fallacy of Exclusion • Argument from the Negative • Appeal to a Lack of Evidence or Argument from Ignorance

FALLACIES OF OMISSION • Hypothesis Contrary to Fact • Trying to prove something in the real world by using imaginary examples alone, or asserting that, if hypothetically X had occurred, Y would have been the result. For instance, suppose an individual asserts that if Einstein had been aborted in utero, the world would never have learned about relativity, or that if Monet had been trained as a butcher rather than going to college, the impressionistic movement would have never influenced modern art. • Contradictory Premises

FALLACIES OF OMISSION • Contradictory Premises • Establishing a premise in such a way that it contradicts another, earlier premise. • Where two premises contradict each other, there can be no interaction and hence no conclusion. Similarly, if the definitions of two terms conflict with or exclude each other, then those two terms cannot be simultaneously ascribed to a single object or event. • IE: If God can do anything, can he make a stone so heavy that he cannot lift it? • The classic example of contradictory premises is the question, "What will happen if an irresistible force meets an immovable object?"

Logical Fallacies • Remember that these types of persuasion are used in media because they appear to be legitimate arguments. • Be aware of these and you will not be fooled!

Logical Fallacies