Search results
Results from the WOW.Com Content Network
Affirmative conclusion from a negative premise (illicit negative) – a categorical syllogism has a positive conclusion, but at least one negative premise. [11] Fallacy of exclusive premises – a categorical syllogism that is invalid because both of its premises are negative. [11]
Reductio ad absurdum, painting by John Pettie exhibited at the Royal Academy in 1884. In logic, reductio ad absurdum (Latin for "reduction to absurdity"), also known as argumentum ad absurdum (Latin for "argument to absurdity") or apagogical arguments, is the form of argument that attempts to establish a claim by showing that the opposite scenario would lead to absurdity or contradiction.
The presence of the formal fallacy does not imply anything about the argument's premises or its conclusion. Both may actually be true or may even be more probable as a result of the argument, but the deductive argument is still invalid because the conclusion does not follow from the premises in the manner described.
In traditional logic, a contradiction occurs when a proposition conflicts either with itself or established fact. It is often used as a tool to detect disingenuous beliefs and bias . Illustrating a general tendency in applied logic, Aristotle 's law of noncontradiction states that "It is impossible that the same thing can at the same time both ...
A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation. [1] [2] It is a statement that, despite apparently valid reasoning from true or apparently true premises, leads to a seemingly self-contradictory or a logically unacceptable conclusion.
An argument is valid if and only if it would be contradictory for the conclusion to be false if all of the premises are true. [3] Validity does not require the truth of the premises, instead it merely necessitates that conclusion follows from the premises without violating the correctness of the logical form.
In classical logics, taking a contradiction (see List of logic symbols) as a premise (that is, taking as a premise the truth of both and ), allows us to prove any statement . Indeed, since p {\displaystyle p} is true, the statement p ∨ q {\displaystyle p\vee q} is true (by generalization).
A fallacy in argumentation that targets the person making an argument rather than the argument itself. ad ignorantium A logical fallacy where a proposition is considered true because it has not been proven false or vice versa. ad infinitum An argument or process that is supposed to continue indefinitely, without ever reaching an end or conclusion.