Contraposition


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Contraposition

 

the law of traditional logic that holds that if from a certain proposition A there follows the proposition B, then from the negation of the proposition B follows the negation of the proposition A (or in the language of conditional propositions: from the truth of the proposition “If A, then B” follows the truth of the proposition “If not B ?, then not- A”).

REFERENCES

Church, A. Vvedenie v matematicheskuiu logiku. Moscow, 1960. (Translated from English.)
Tarski, A. Vvedenie v logiku i metodologiiu deduktivnykh nauk. Moscow, 1948. (Translated from English.)
References in periodicals archive ?
But if, as the Humean will have it, chances supervene on histories of occurrence, statements about histories of occurrence must entail statements about chances, and by contraposition (negations of) statements about chances must entail (perhaps infinite disjunctions of negations of) statements about histories of occurrence.
Indeed, Kierkegaard's contraposition of faith and ethics, with the former very much in the preferred position, owes more to his Lutheran heritage than to the thought world of ancient Israel (as he may well have recognized).
Much of the power of Thucydides' prose style derives from his use of antithesis, that is, the contraposition of claim and counterclaim in close and rhetorically effective order.
83), a contraposition that would be central to Alfieri's later work (not by chance do the earliest parts of Misogallo date from 1789-1791), was influenced by the contemporary political climate in England, by a public opinion that was now decidedly anti-revolutionary, and by Alfieri's contact (through the Countess of Albany) with Horace Walpole, as well as by his acquaintance with Burke's Reflections on the Revolution in France.
And if it is not acceptable, then nor is the contraposition of it upon which Boghossian's step from (ii) to (iii) depends.
By the contraposition of (1) and the comments in the two previous paragraphs, the standard commodity of a valid Walrasian system must be a real commodity.
On the strength of the immediate testimony of our bodies, we are able to say what no disembodied onlooker would have a cause for saying: [that life is] self-centered individuality, being for itself and in contraposition to all the rest of the world, with an essential boundary dividing `inside' and outside'--notwithstanding, nay, on the basis of the actual exchange" (p.
I have argued elsewhere that the contraposition of "new social movements" to orthodox Marxism misreads the history of social movements and oversimplifies the history of socialism.
While Loevinger and the antitrusters had established a record of vigorous and responsible enforcement, after the contraposition the record pales.
Such contraposition may be justifiable in communist countries; but it does not make much sense in developing countries.
UANI is particularly disturbed that "Millionaire" appears to have recently transported crude oil from an Egyptian port to Tartus, Syria -- an action in direct contraposition to the multinational sanctions put in place in response to the Assad regime's ongoing and brutal crackdown on the Syrian people.
That program provides a fixed cast, currently of 112 marketed drugs, mostly by lower values than CMED consumer prices set for sale in pharmacies and drugstores, in contraposition to the Aqui tem Farmacia Popular do Brasil program which is composed by a more restricted cast and to meet specific health conditions.