deductive validity
1Validity — The term validity (also called logical truth, analytic truth, or necessary truth) as it occurs in logic refers generally to a property of particular statements and deductive arguments. Although validity and logical truth are synonymous concepts,… …
2Deductive reasoning — Deductive reasoning, also called deductive logic, is reasoning which constructs or evaluates deductive arguments. Deductive arguments are attempts to show that a conclusion necessarily follows from a set of premises or hypotheses. A deductive… …
3Deductive system — A deductive system (also called a deductive apparatus of a formal system) consists of the axioms (or axiom schemata) and rules of inference that can be used to derive the theorems of the system.[1] Such a deductive system is intended to preserve… …
4Deductive fallacy — A deductive fallacy is defined as a deductive argument that is invalid. The argument itself could have true premises, but still have a false conclusion.[1] Thus, a deductive fallacy is a fallacy where deduction goes wrong, and is no longer a… …
5hypothetico-deductive method — /huy peuh thet i koh di duk tiv/, Logic. a method in which a hypothetical model based on observations is proposed and is then tested by the deduction of consequences from the model. [1925 30; HYPOTHETIC(AL) + O + DEDUCTIVE, prob. as trans. of It… …
6Logic — For other uses, see Logic (disambiguation). Philosophy …
7Argument — This article is about the subject as it is studied in logic and philosophy. For other uses, see Argument (disambiguation). In philosophy and logic, an argument is an attempt to persuade someone of something, by giving reasons or evidence for… …
8formal logic — the branch of logic concerned exclusively with the principles of deductive reasoning and with the form rather than the content of propositions. [1855 60] * * * Introduction the abstract study of propositions, statements, or assertively used …
9First-order logic — is a formal logical system used in mathematics, philosophy, linguistics, and computer science. It goes by many names, including: first order predicate calculus, the lower predicate calculus, quantification theory, and predicate logic (a less… …
10logic — logicless, adj. /loj ik/, n. 1. the science that investigates the principles governing correct or reliable inference. 2. a particular method of reasoning or argumentation: We were unable to follow his logic. 3. the system or principles of… …
