hog cholera

or swine fever

Often fatal viral disease of swine in Europe, North America, and Africa, transmitted by vehicles used to carry pigs, people dealing with them, and uncooked garbage in feed. Fever progresses to symptoms that include appetite loss; affected eyes and digestive tract; respiratory difficulty; rash; and inflamed mouth and throat. The pig moves reluctantly and staggers; later it cannot rise; coma follows. Antiserum is rarely effective. Survivors become chronically ill and can spread the virus. Illness must be reported, infected animals slaughtered, and quarantine instituted. A vaccine can control it. The African strain causes death sooner and has no effective prevention or treatment.

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School of economic thought largely centred in Britain that originated with Adam Smith and reached maturity in the works of David Ricardo and John Stuart Mill. The theories of the classical school were mainly concerned with the dynamics of economic growth. Reacting against mercantilism, classical economics emphasized economic freedom. It stressed ideas such as laissez-faire and free competition. Many of the fundamental principles of classical economics were set forth in Smith's Wealth of Nations (1776), in which he argued that a nation's wealth was greatest when its citizens pursued their own self-interest. Neoclassical economists such as Alfred Marshall showed that the forces of supply and demand would ration economic resources to their most effective uses. Smith's ideas were elaborated and refined by Ricardo, who formulated the principle that the price of goods produced and sold under competitive conditions tends to be proportionate to the labour costs incurred in producing them. Mill's Principles of Political Economy (1848) gave the ideas greater currency by relating them to contemporary social conditions. Among those who have modified classical economics to reach very different conclusions are Karl Marx and John Maynard Keynes.

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The word classical has several meanings:

Culture

• Classical antiquity and the study of "the classics", refers to the culture of Ancient Greece or Rome
• "High classical" refers to Greek art associated mainly with Athens and the works atop the Acropolis
• "Classical Chinese" or "classical Indian" culture refers to a perceived apex in the development of a society or of its arts and sciences
• "Classical French" culture refers specifically to the 18th century, rather than Ancient Greece or Rome. This causes confusions in translation.
• Classical language

The arts

Pertaining to the arts (painting, music, literature, etc.), the word classical often refers to a specific time period or artistic style:

• Classical architecture originated from Roman and Greek construction methods, which were later used as a model for "neo–" and "revival" architectural styles
• Classical music
• Classical music era
• Classical dance, or ballet
• Classicism
• Classical education refers to the educational tradition based upon the trivium and quadrivium.
• Classical philosophy
• Indian classical music
• Classical Indian dance
• Classical liberalism
• Non-Western classical music

Science

The word 'classical' is applied to any mode of scientific thought prevalent up to the time of some radical new innovation, or any scientific area of study that has well established roots, typically pre-nineteenth century.

• Classical mechanics, in physics, as founded by e.g. Galileo, Newton and formalized by Hamilton and Lagrange (developed before the advent of modern quantum mechanics) (see also the page about classical physics)
• Classical mechanics is Newtonian physics, i.e. physics as it was before special relativity and quantum mechanics. In other words, the limit of physics as c² goes to infinity and h goes to zero.
• Semiclassical physics, an approximate solution to a problem generated by assuming that for parts of the system, the results of classical physics does not differ too much from that of the quantum mechanics method.
• Classical electrodynamics, as formalized by Maxwell
• Classical logic, in mathematical logic includes the family of bivalent logics where every proposition is either true or false.
• "Classical control theory" applies control theory to analog systems. Based on classical math methods such as Laplace transforms and calculus, as opposed to the more recent digital control systems theory - based on more modern methods such as the z transforms.
• Classical economics is the school of the first economists starting with Adam Smith. Its modern successor is neoclassical economics

See also

• Classics (disambiguation)
• Neoclassical