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Logic and rhetoric
In logic, an argument (Latin argumentum: "proof, evidence, token, subject, contents") is a connected series of statements or propositions, called premises, that are intended to provide support, justification or evidence for the truth of another statement, the conclusion.
A deductive argument asserts that the truth of the conclusion is a logical consequence (C) of the premises (P); an inductive argument asserts that the truth of the conclusion is supported by the premises. Deductive arguments are judged by the properties of validity and soundness. An argument is valid if and only if the conclusion is a logical consequence of the premises. A sound argument is a valid argument with true premises.
For example in this syllogism, the following is a valid argument (because the conclusion follows from the premises) and also sound (because additionally the premises are true):
- P1: All Greeks are human.
- P2: All humans are mortal.
- C: Therefore, all Greeks are mortal.
Invalid arguments involve several fallacies that do not satisfy the idea that an argument must deduce a conclusion that is logically coherent. A common example is the non sequitur, where the conclusion is completely disconnected from the premises.
Not all fallacious arguments are invalid. In a circular argument, the conclusion actually is a premise, so the argument is trivially valid. It is completely uninformative, however, and doesn't really prove anything.
In debate or discourse
In everyday practice an argument may be structured into talking points, issues that are supposed to help support said argument. Talking points based on distorted or false reality are often used in propaganda venues and political debates in tandem with loaded language to sway the course of a debate towards a predetermined conclusion. Such tactics turn an argument into emotional manipulation (having an argument) as opposed to logical exercise (making an argument).