Page:Encyclopædia Britannica, Ninth Edition, v. 10.djvu/574

in accordance with his instructions, proclaimed joint emperors; and after the failure of a proposed treaty by which Caracalla was to retain Europe and western Africa, and Geta Asia and Egypt, Caracalla, on the pretence of a desire for reconciliation, arranged a meeting with his brother in his mother’s apartments, and by means of assassins murdered him in her presence (212). His name was obliterated from all public inscriptions; all coins bearing his effigy were to be destroyed; and the use of his name, either in conversation or in writing, was forbidden under pain of death.

GETHSEMANE. See Jerusalem.

GEULINCX, Arnold (1625–1669), one of the most distinguished of the earlier Cartesians, was born at Antwerp in 1625. Few details are known with regard to his life, and his more important works are extremely rare. He studied philosophy and medicine at the university of Louvain, and took there the degree of doctor. For twelve years he continued at the same university as lecturer, and was noted as one of the most successful teachers. For what reason he left is quite uncertain, but he seems to have been obliged to fly from Louvain and to take refuge in Leyden, where he appears to have been in the utmost distress. Only the generous assistance of a friend, by name Heidanus, prevented his death from absolute want of means. At Leyden he entered the Protestant Church, having been previously a Catholic, and it has been supposed that his flight from Louvain was due to doubts excited there as to his orthodoxy. This, however, is merely conjecture. In 1663, through his friend Heidanus, he obtained leave to lecture at Leyden, and devoted himself with the utmost zeal to his new duties. He died in 1669. His most important works were published posthumously. During his lifetime there seem to have been made public only the theses which he defended on graduating at Louvain (Saturnalia, seu quæstiones quodlibeticæ in utramque partem disputatæ, 2d ed. 1665). The Metaphysica vera, 1691, and the Γνῶθι σεαυτόν, sive Ethica, post tristia auctoris fata, 1696 (first part, 1665), are the works by which he is known in the history of philosophy. In addition to these were published Physica Vera, Logica restituta, and Annotata in Principia Philosophiæ R. Cartesii. Geulincx takes up principally the doctrine, left in an obscure and unsatisfactory state by Descartes, of the relation between soul and body. Extension and thought, the essences of spiritual and corporeal natures, are absolutely distinct, and cannot act upon one another. External facts are not the causes of mental states, nor are mental states the causes of physical facts. So far as the physical universe is concerned, we are merely spectators. The influence we seem by will to exercise over bodies is only apparent; volition and action only accompany one another. I cannot be the author of any state of which I am unconscious, for my very nature is consciousness; but I am not conscious of the mechanism by which bodily motion is produced, hence I am not the author of bodily motion. Body and mind are like two clocks which act together, because at each instant they are adjusted by God. A physical occurrence is but the occasion on which God excites in me a corresponding mental state. Geulincx is thus definitely the originator of the theory called Occasionalism. But the principles on which that theory was founded compelled a further advance. God, who is the cause of the concomitance of bodily and mental facts, is in truth the sole cause in the universe. No fact contains in itself the ground of any other; the existence of the facts is due to God, their sequence and co-existence are also due to him. He is the ground of all that is. My desires or volitions and my thoughts are thus the desires, volitions, or thoughts of God. Apart from God, the finite being has no reality. Geulincx is thus the precursor of Spinoza, and, like Spinoza, he gave out his final results under the title of Ethics. Descartes had left untouched, or nearly so, the difficult problem of the relation between the universal element or thought and the particular desires or inclinations. All these are regarded by Geulincx as modes of the divine thought and action, and accordingly the end of human endeavour is the end of divine will, or the realization of reason. The love of right reason is the supreme virtue, whence flow the cardinal virtues, diligence, obedience, justice, and humility. Liberty is obedience to reason; nemo servit qui rationi servit.

Geulincx has not directly touched the problem which evidently must have caused the greatest difficulty to the Cartesians,—how we perceive extended reality,—though he plainly indicates the opinion that we do not perceive it, but have the idea of it from God. He thus carried out to their extreme consequences the irreconcilable elements in the Cartesian metaphysics, and his works have the peculiar value attaching to the vigorous development of a one-sided principle. The abrupt contradictions to which such development leads of necessity compels revision of the principle itself.

See Damiron, Phil. en France au 17^me siècle, 1816; Bouillier, His. de la Phil. Cartesienne, i. ch. 14; Erdmann, Versuch einer Gesch. d. neu. Phil., i., b., sec. 2; Ritter, Gesch. d. Phil., xi. pp. 97–169 (Ritter’s account of Geulincx is the fullest in any history of philosophy); K. Fischer, Gesch. d. neu. Phil., i. 2, 11–27.

GEX, a town of France, the chief town of an arrondissement in the department of Ain, is beautifully situated, 2000 feet above sea-level, at the base of the Jura chain on the Journant, 3 miles from the Swiss frontier, and 10 miles N.W. of Geneva. It has tanneries, saw-mills, and corn-mills, and a considerable trade in cheese and wine. The town gives its name to the old Pays de Gex, situated between the Alps and the Jura, which was successively under the protection of the Swiss, the Genevese, and the counts of Savoy, until in 1602 it came into the possession of France, retaining, however, until the Revolution its old independent jurisdiction, with Gex as its chief town. The population of the town in 1876 was 1469.

Fig. 1.
Fig. 2.
Observed.	A	Calculated.
186°		225°
230°		241°
C		249°
251°		255°
D
255°		266°
259°		278°
	B

GEYSERS, Geisers, or Geisirs, are fountains of a peculiar construction, in virtue of which they shoot up into the air, at more or less regular intervals of time, a column of heated water and steam or of mud. Those of Iceland have been known at least from the time of Saxo Grammaticus, who briefly mentions them in his Danorum regum historiæ; but no satisfactory explanation of the phenomena was advanced till near the middle of the present century, when Bunsen brought his scientific knowledge and power of investigation to bear on the subject. Sir George Mackenzie, in his Travels in Iceland, 1811, had written as follows:—“Let us suppose a cavity C (fig. 1), communicating with the pipe PQ, filled with boiling water to the height AB, and that the steam above this line is confined so that it sustains the water to the height P. If we suppose a sudden addition of heat to be applied under the cavity C, a quantity of steam will be produced which, owing to the great pressure, will be evolved in starts causing the noises like discharges of artillery, and the shaking of the ground.” He admitted that even to his own mind this could be only a partial explanation of the facts of the case, and that he was unable to account for the frequent and periodical production of the necessary heat; but he has the credit of hitting on what is certainly the proximate cause—the sudden evolution of steam. By Bunsen’s theory the whole difficulty is solved, as is beautifully demonstrated by the artificial geyser designed by Professor J. H. J. Müller of