Source: Mathematical Thought from Ancient to Modern Times (1972), p. 441.
“The minimum principle that unified the knowledge of light, gravitation, and electricity of Hamilton's time no longer suffices to relate these fundamental branches of physics. Within fifty years of its creation, the belief that Hamilton's principle would outlive all other physical laws of physics was shattered. Minimum principles have since been created for separate branches of physics… but these are not only restricted… but seem to be contrived…
A single minimum principle, a universal law governing all processes in nature, is still the direction in which the search for simplicity is headed, with the price of simplicity now raised from a mastery of differential equations to a mastery of the calculus of variations.”
Source: Mathematical Thought from Ancient to Modern Times (1972), p. 442.
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Morris Kline 42
American mathematician 1908–1992Related quotes

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1840s
Context: The hon. Gentleman has said, in a most extraordinary manner, that our security for peace at the present day is the desire of nations to keep at home. There is a great difference between nationality and race. Nationality is the principle of political independence. Race is the principle of physical analogy, and you have at this moment the principle of race— not at all of nationality— adopted by Germany, the very country to which the hon. Member for the West Riding referred.

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[Léon Brillouin, Science and Information Theory, second edition, Academic Press, New York, 1962, 0-48643-918-6, 304]