In logic, an argument is valid if and only if its conclusion is logically entailed by its premises and each step in the argument is logical. A formula is valid if and only if it is true under every interpretation, and an argument form (or schema) is valid if and only if every argument of that logical form is valid.

Read more about Validity:  Validity of Arguments, Valid Formula, Validity of Statements, Validity and Soundness, Satisfiability and Validity, Preservation, N-Validity, See Also

Other articles related to "validity":

Validity - See Also
... Logic portal Entailment Grounds of validity of scientific reasoning Mathematical fallacies Soundness ...
Multitrait-multimethod Matrix
... (MTMM) matrix is an approach to examining Construct Validity developed by Campbell and Fiske(1959) ... when examining a construct's validity through the MTMM matrix, which are as follows 1 ... Evaluation of convergent validity — Tests designed to measure the same construct should correlate highly amongst themselves ...
Anne Anastasi - Methods
... the methodological principles of norms, reliability, validity, and item analysis ... of the tests, particularly as they apply to norms, validity, and reliability ... In contrast with the belief that there are three kinds of validity - content validity, criterion validity, and construct validity - Anastasi espoused to the then-growing belief of the mid-1980s that many more ...
Security Advisory Opinion - Validity Period
... The validity of the clearance (which specifies a deadline for the time a visa could be issued) is based on its type, and ranges between three and 48 months ... During the period of validity, posts can usually issue another visa for the applicant without requesting a new SAO if the applicant's circumstances ...

Famous quotes containing the word validity:

    The hardiest skeptic who has seen a horse broken, a pointer trained, or has visited a menagerie or the exhibition of the Industrious Fleas, will not deny the validity of education. “A boy,” says Plato, “is the most vicious of all beasts;” and in the same spirit the old English poet Gascoigne says, “A boy is better unborn than untaught.”
    Ralph Waldo Emerson (1803–1882)

    Once one is caught up into the material world not one person in ten thousand finds the time to form literary taste, to examine the validity of philosophic concepts for himself, or to form what, for lack of a better phrase, I might call the wise and tragic sense of life.
    F. Scott Fitzgerald (1896–1940)

    It does not follow, because our difficulties are stupendous, because there are some souls timorous enough to doubt the validity and effectiveness of our ideals and our system, that we must turn to a state controlled or state directed social or economic system in order to cure our troubles.
    Herbert Hoover (1874–1964)