160 Thus, for instance, _G. Biel_ (ob. 1495), the “last of the schoolmen,” gives us his doctrine of Political Economy, in a work on Dogmatic Theology, in the chapter on Penance, his starting point being the inquiry, how the economic damage caused by the sinner may be repaired. _Roscher_, Geschichte der Nationalökonomik in Deutchland, 1074, I, 23. The Melittotheologia, Arachnotheologia of later times! A recent attempt in this direction has been made by _Ad. Müller_, Nothwendigkeit einer theologischen Grundage der gesammten Staatswissenschaften und der Staatswirthschaft insbesondere (1819), i.e., “necessity of a theological basis for all political science, and especially for Political Economy.” He divides political science into two parts: the science of law, and the science of wisdom, embracing under the latter denomination, politics, Political Economy, etc. Law emanates from God, as supreme judge; the science of wisdom from God, as our Supreme Father. 161 Abstraction is indulged in on a large scale, when a number of elements which are always found combined in life, are here separated and examined apart. It is precisely thus that anatomy proceeds, dissecting each member of the human frame, separating the bones, ligaments and muscles from one another, thus becoming the necessary preparatory school to physiology. 162 Thus, for instance, _Canard_, Principes d’Economie politique (1801). Also _Kröncke_, in several of his works, and _Count Buquoy_, in his Theorie der Nationalwirthschaft (1816), p. 333 ff.; _Lang_, Grundlinien einer politischen Arithmetik, Charkow, 1811, and more especially _v. Thünen_, Der isolirte Staat, vol. I (1842), vol. II, 1850. See my criticism of his method in _Birnbaum’s_ Georgika, 1869, 77 ff. _Voa Thünen’s_ first volume is an essay towards a geometrical exposition of the science. See also _Rau_, Lehrbuch I, § 154, appendix; _von Mangoldt_, Grundriss der Volkswirthschaftslehre (1862); _Cazaux_, Elements d’Economie privée et Principes mathématiques de la Théorie des Richesses (1838); _F. Fuoco_, Saggi economici (1827) II, 61 ff. _Walras_, Eléments d’Econ. politique pure (1874). _Jevons_ has recently endeavored to give Political Economy a mathematical basis by reducing the objects of which it treats to the calculable feelings of pleasure (+) and pain (-). The duration of a feeling is treated as an abscissa, its intensity as the ordinate of a curve, and its quantity as the area. Future feelings are reduced to present ones, by allowing for their distance, and the uncertainty of their occurrence. All this, however, is rather curious than scientifically useful. _ 163 Herbart_, Ueber die Möglichkeit und Nothwendigkeit, Mathematik auf Psychologie anzuwenden; Kleinere Schriften, II, 417.