Logic and fallacy

If Bill Gates owns Fort Knox, then he is rich. Bill Gates is rich. Therefore, he owns Fort Knox.

Logic and fallacy

The self-reliant fallacy In philosophythe term logical fallacy properly refers to a formal fallacy—a flaw in the structure of a deductive argumentwhich renders the argument invalid. However, it is often used more generally in informal discourse to mean an argument that is problematic for any reason, and thus encompasses informal fallacies as well as formal fallacies—valid but unsound claims or poor non-deductive argumentation.

Logic and fallacy

The presence of a formal fallacy in a deductive argument does not imply anything about the argument's premises or its conclusion see fallacy fallacy. Both may actually be true, or even more probable as a result of the argument e. By extension, an argument can contain a formal fallacy even if the argument is not a deductive one; for instance an inductive argument that incorrectly applies principles of probability or causality can be said to commit a formal fallacy.

Affirming the consequent[ edit ] Any argument that takes the following form is a non sequitur If A is true, then B is true. Therefore, A is true. Even if the premise and conclusion are all true, the conclusion is not a necessary consequence of the premise. This sort of non sequitur is also called affirming the consequent.

An example of affirming the consequent would be: If Jackson is a human Athen Jackson is a mammal. B Jackson is a mammal. B Therefore, Jackson is a human.

A While the conclusion may be true, it does not follow from the premise: Humans are mammals Jackson is a mammal Therefore, Jackson is a human The truth of the conclusion is independent of the truth of its premise — it is a 'non sequitur', since Jackson might be a mammal without being human.

He might be an elephant. Affirming the consequent is essentially the same as the fallacy of the undistributed middle, but using propositions rather than set membership. Denying the antecedent[ edit ] Another common non sequitur is this: If A is true, then B is true.

Therefore, B is false. While B can indeed be false, this cannot be linked to the premise since the statement is a non sequitur.

Fallacy: Fallacy, in logic, erroneous reasoning that has the appearance of soundness. In logic an argument consists of a set of statements, the premises, whose truth supposedly supports the truth of a single statement called the conclusion of the argument. An argument is deductively valid when the truth of. noun, plural fal·la·cies. a deceptive, misleading, or false notion, belief, etc.: That the world is flat was at one time a popular fallacy. a misleading or unsound argument. Fallacy of Propositional Logic. Taxonomy: Logical Fallacy > Formal Fallacy > Fallacy of Propositional Logic Subfallacies: Affirming a Disjunct, Affirming the Consequent, Commutation of Conditionals, Denying a Conjunct, Denying the Antecedent, Improper Transposition Alias: Fallacy of sentential logic * Exposition: In logic, a proposition―or, "statement"―is a sentence that is either true .

This is called denying the antecedent. An example of denying the antecedent would be: If I am Japanese, then I am Asian. I am not Japanese.Videos, articles, books and blogs to exercise your mind. Descriptions of common fallacies. Dr. Michael C.

Labossiere, the author of a Macintosh tutorial named Fallacy Tutorial Pro , has kindly agreed to allow the text of . A logical fallacy is a flaw in reasoning.

Logical fallacies are like tricks or illusions of thought, and they're often very sneakily used by politicians and the media to fool people. Don't be fooled! This website has been designed to help you identify and call out dodgy logic wherever it . Transitive Property of Equality. The following property: If a = b and b = c, then a = kaja-net.com of the equivalence properties of equality..

Note: This is a property of equality and inequalities.(Click here for the full version of the transitive property of inequalities.) One must be cautious, however, when attempting to develop arguments using the transitive property in other settings.

The opposite of this fallacy is the postmodern fallacy of Mind Blindness (also, the Autist's Fallacy), a complete denial of any normal human capacity for "Theory of Mind," postulating the utter incommensurability and privacy of minds and thus the impossibility of ever knowing or truly understanding another's thoughts, emotions, motivations or.

You presented two alternative states as the only possibilities, when in fact more possibilities exist.

Logic and fallacy
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