extreme consequences.  The course of philosophy takes first a theological direction in the earlier occasionalists, then a metaphysical (naturalistic) trend in Spinoza, to renew finally, in Malebranche, the first of these movements in opposition to the second.  The Cartesian school, as a whole, however, exhibits a tendency toward mysticism, which was concealed to a greater or less extent by the rationalistic need for clear concepts, but never entirely suppressed.

Although the real interaction of body and mind be denied, some explanation must, at least, be given for the appearance of interaction, i.e. for the actual correspondence of bodily and mental phenomena.  Occasionalism denotes the theory of occasional causes.  It is not the body that gives rise to perception, nor the mind that causes the motion of the limbs which it has determined upon—­neither the one nor the other can receive influence from its fellow or exercise influence upon it; but it is God who, “on the occasion” of the physical motion (of the air and nerves); produces the sensation (of sound), and, “at the instance” of the determination of the will, produces the movement of the arms.  The systematic development and marked influence of this theory, which had already been more or less clearly announced by the Cartesians Cordemoy and De la Forge,[1] was due to the talented Arnold Geulincx (1624-69), who was born at Antwerp, taught in Lyons (1646-58) and Leyden, and became a convert to Calvinism.  It ultimately gained over the majority of the numerous adherents of the Cartesian philosophy in the Dutch universities,—­Renery (died 1639) and Regius (van Roy; Fundamenta Physicae, 1646; Philosophia Naturalis, 1661) in Utrecht; further, Balthasar Bekker (1634-98; The World Bewitched, 1690), the brave opponent of the belief in angels and devils, of magic, and of prosecution for witchcraft,—­in the clerical orders in France and, finally, in Germany.

[Footnote 1:  Gerauld de Cordemoy, a Parisian advocate (died 1684, Dissertations Philosophiques, 1666), communicated his occasionalistic views orally to his friends as early as 1658 (cf.  L. Stein in the Archiv fuer Geschichte der Philosophie, vol. i., 1888, p. 56).  Louis de la Forge, a physician of Saumur, Tractatus de Mente Humana, 1666, previously published in French; cf.  Seyfarth, Gotha, 1887.  But the logician, Johann Clauberg, professor in Duisburg (1622-65; Opera, edited by Schalbruch, 1691), is, according to the investigations of Herm.  Mueller (J.  Clauberg und seine Stellung im Cartesianismus, Jena, 1891), to be stricken from the list of thinkers who prepared the way for occasionalism, since in his discussion of the anthropological problem (corporis et animae conjunctio) he merely develops the Cartesian position, and does not go beyond it.  He employs the expression occasio, it is true, but not in the sense of the occasionalists.  According to Clauberg the bodily phenomenon becomes the stimulus or “occasion” (not for God, but) for the soul to produce from itself the corresponding mental phenomenon.]