Necessity
Some implications of the displacement current follow, which agree with experimental observation, and with the requirements of logical consistency for the theory of electromagnetism.
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Famous quotes containing the word necessity:
“The necessity of poetry has to be stated over and over, but only to those who have reason to fear its power, or those who still believe that language is “only words” and that an old language is good enough for our descriptions of the world we are trying to transform.”
—Adrienne Rich (b. 1929)
“If necessity is the mother of invention, then resourcefulness is the father.”
—Beulah Louise Henry, U.S. inventor. As quoted in Feminine Ingenuity, ch. 13, by Anne L. MacDonald (1992)
“To expect to increase prices and then to maintain them at a higher level by means of a plan which must of necessity increase production while decreasing consumption is to fly in the face of an economic law as well established as any law of nature.”
—Calvin Coolidge (1872–1933)