Concept
Term logic
Related concepts (28)
Traditional grammar
Traditional grammar (also known as classical grammar) is a framework for the description of the structure of a language. The roots of traditional grammar are in the work of classical Greek and Latin philologists. The formal study of grammar based on these models became popular during the Renaissance. Traditional grammars may be contrasted with more modern theories of grammar in theoretical linguistics, which grew out of traditional descriptions.
Obversion
In traditional logic, obversion is a "type of immediate inference in which from a given proposition another proposition is inferred whose subject is the same as the original subject, whose predicate is the contradictory of the original predicate, and whose quality is affirmative if the original proposition's quality was negative and vice versa". The quality of the inferred categorical proposition is changed but the truth value is the same to the original proposition.
Transposition (logic)
In propositional logic, transposition is a valid rule of replacement that permits one to switch the antecedent with the consequent of a conditional statement in a logical proof if they are also both negated. It is the inference from the truth of "A implies B" to the truth of "Not-B implies not-A", and conversely. It is very closely related to the rule of inference modus tollens. It is the rule that where "" is a metalogical symbol representing "can be replaced in a proof with".
Logical constant
In logic, a logical constant or constant symbol of a language is a symbol that has the same semantic value under every interpretation of . Two important types of logical constants are logical connectives and quantifiers. The equality predicate (usually written '=') is also treated as a logical constant in many systems of logic.
Generalized quantifier
In formal semantics, a generalized quantifier (GQ) is an expression that denotes a set of sets. This is the standard semantics assigned to quantified noun phrases. For example, the generalized quantifier every boy denotes the set of sets of which every boy is a member: This treatment of quantifiers has been essential in achieving a compositional semantics for sentences containing quantifiers. A version of type theory is often used to make the semantics of different kinds of expressions explicit.
Premise
A premise or premiss is a proposition—a true or false declarative statement—used in an argument to prove the truth of another proposition called the conclusion. Arguments consist of a set of premises and a conclusion. An argument is meaningful for its conclusion only when all of its premises are true. If one or more premises are false, the argument says nothing about whether the conclusion is true or false. For instance, a false premise on its own does not justify rejecting an argument's conclusion; to assume otherwise is a logical fallacy called denying the antecedent.
Prior Analytics
The Prior Analytics (Ἀναλυτικὰ Πρότερα; Analytica Priora) is a work by Aristotle on reasoning, known as syllogistic, composed around 350 BCE. Being one of the six extant Aristotelian writings on logic and scientific method, it is part of what later Peripatetics called the Organon. The term analytics comes from the Greek words analytos (ἀναλυτός, 'solvable') and analyo (ἀναλύω, 'to solve', literally 'to loose'). However, in Aristotle's corpus, there are distinguishable differences in the meaning of ἀναλύω and its cognates.
Predicable
Predicable (Lat. praedicabilis, that which may be stated or affirmed, sometimes called quinque voces or five words) is, in scholastic logic, a term applied to a classification of the possible relations in which a predicate may stand to its subject. It is not to be confused with 'praedicamenta', the scholastics' term for Aristotle's ten Categories. The list given by the scholastics and generally adopted by modern logicians is based on development of the original fourfold classification given by Aristotle (Topics, a iv.