necessary


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Related to necessary: Necessary and sufficient

necessary

1. Logic
a. (of a statement, formula, etc.) true under all interpretations or in all possible circumstances
b. (of a proposition) determined to be true by its meaning, so that its denial would be self-contradictory
c. (of a property) essential, so that without it its subject would not be the entity it is
d. (of an inference) always yielding a true conclusion when its premises are true; valid
e. (of a condition) entailed by the truth of some statement or the obtaining of some state of affairs
2. Philosophy (in a nonlogical sense) expressing a law of nature, so that if it is in this sense necessary that all As are B, even although it is not contradictory to conceive of an A which is not B, we are licensed to infer that if something were an A it would have to be B
References in classic literature ?
If, on the contrary, she had been contented with writing to her master, it would only be necessary to devise measures for intercepting the letter.
The postmaster was compelled to acknowledge that there could be no objection, provided nothing but a necessary line was added to the address, provided nobody touched the letter but himself, and provided the precious time of the post-office was not suffered to run to waste.
What reasonable cause of apprehension can be inferred from a power in the Union to prescribe regulations for the militia, and to command its services when necessary, while the particular States are to have the SOLE AND EXCLUSIVE APPOINTMENT OF THE OFFICERS?
With what color of propriety could the force necessary for defense be limited by those who cannot limit the force of offense?
It is worse than in vain; because it plants in the Constitution itself necessary usurpations of power, every precedent of which is a germ of unnecessary and multiplied repetitions.
For it is not necessary that a subject receptive of the qualities should always have either the one or the other; that which has not yet advanced to the state when sight is natural is not said either to be blind or to see.
iv) Statements opposed as affirmation and negation belong manifestly to a class which is distinct, for in this case, and in this case only, it is necessary for the one opposite to be true and the other false.
The movement of peoples from west to east was to be succeeded by a movement of peoples from east to west, and for this fresh war another leader was necessary, having qualities and views differing from Kutuzov's and animated by different motives.
Alexander I was as necessary for the movement of the peoples from east to west and for the refixing of national frontiers as Kutuzov had been for the salvation and glory of Russia.
It will be necessary, therefore, to wait for the moment when her passage in perigee shall coincide with that in the zenith.
But, in order that the moon should reach the zenith of a given place, it is necessary that the place should not exceed in latitude the declination of the luminary; in other words, it must be comprised within the degrees 0@ and 28@ of lat.
Poetry, indeed, may perhaps be thought an exception; but then it demands numbers, or something like numbers: whereas, to the composition of novels and romances, nothing is necessary but paper, pens, and ink, with the manual capacity of using them.