OTHER METHODS. In actual practice a large number of complicated combinations of the de ductive and inductive methods arc used in economies. Induction in its quantitative aspect gives rise to the statistical method. No school of political economy has ever disputed the im and value of statistics, and in the last few years it has made more rapid progress per haps than any other branch of the science. This is due to the increased public expenditures in statistical investigations, and the impetus given to the improvement of the study by such associa tions as the International Statistical Institute, the Royal Statistical Society, the American Statistical Association. So great has been the development of statistical technique at the hands of such men as Quetelet, Bertillon, Engels, Von Mayr, Edgeworth (to whom should be added front other sciences, Gallon, Venn, Karl Pearson, etc.), that the technique of quantitative induc tion constitutes in reality a new branch of science. (See STATISTICS.) Deduction in its quantitative aspect gives rise to the mathematical method of political economy, which at the pres ent time is employed to a greater or less extent in all branches of economic theory, particularly in the investigation of prices, incidence of taxa tion, etc. Opinions differ upon the usefulness of mathematics except in statistics. Mathemat ical diagrams for purposes of illustration, at least, have undoubtedly made a permanent place for themselves in the science, but the utility of algebraic mathematics, except for him who com putes them, is doubtful.
See MERCANTILISM; PHYSIOCRATS ; INTEREST; RENT; LABOR; FINANCE; SOCIOLOGY; PROTEC TION; FREE TRADE; LAISSEZ-FAIRE; SOCIALISM; TRADE UNIONS ; VALUE; USURY.
The most important works of the earlier English economists are: Smith, TVcalth of (London, 1776; many later editions) ; Say, Trait treconomie polit iquc (Paris, 1803) ; Ricardo, Principles of Political Econom y and Taxation (London, 1817); Mal thus. Political Economy 1820) ; Mill, Principles of Political Economy with Sonic of Their Applications to Social Philosophy (ib., 1848) ; Senior, An. Outline of the Science of l'olitical Economy (ib., 1850). Prominent mod ern general treatises are: Marshall, Prin ciples of Political Economy (4th ed., ib., 1898) ; Nicholson, Principles of Political Econ omy (New York, 1893-1901) ; Ely, Outlines of Economics (New York, 1893) ; Wagner, Lehr ond Handbuch der politischen, Oekonomie (Leip zig, 1883-1901). The new theories are best repre sented by Wiese•, Natural l'alue (London, 1893) : Boehm-Bawerk. Positive Theory of Capi tal, Eng. trans. (ib., 1892) ; Clark, The Distribution of Wealth (New York, 1899). The most important socialistic contribution to eco nomies is Marx, Capital (London, 1887). Con sult, also: Ingram, A History of Political Economy (New York, 1888) ; Ashley, An Intro duction to English Economic History and Theory (London, 1888-93) ; l'algrave, Dictionary of Political Economy (ib., 1894-99).