that a simplification was needed here; but by erroneously reducing outer perception to inner perception, he reached the absurd conclusion of denying the external world.  The true course is just the opposite of this—­the one already taken by the Bishop of Cork, Peter Browne (died 1735; The Procedure, Extent, and Limits of the Human Understanding, 1728):  understanding and reflection must be reduced to sensation.  All psychical functions are transformed sensations.  The soul has only one original faculty, that of sensation; all the others, theoretical and practical alike, are acquired, i.e., they have gradually developed from the former.  Condillac is related to Locke as Fichte to Kant; in the former case the transition is mediated by Browne, in the latter by Reinhold.  Each crowns the work of his predecessor with a unifying conclusion; each demands and offers a genetic psychology which finds the origin of all the spiritual functions—­from sensation and feelings of pleasure and pain up to rational cognition and moral will—­in a single fundamental power of the soul.  But there is a great difference, materially as well as formally, between these kindred undertakings, a difference corresponding to that between Locke’s empiricism and Kant’s idealism.  The idea of ends, which controls the course of thought in Fichte as in Leibnitz, is entirely lacking in Condillac; that which is first in time, sensation, is for the Science of Knowledge and the Monadology only the beginning, not the essence, of psychical activity, while Condillac makes no distinction between beginning and ground, but expressly identifies principe and commencement.  With Fichte and Leibnitz sensation is immature thought, with Condillac thought is refined sensation.  The former teach a teleological, the latter a mechanical mono-dynamism.  The Science of Knowledge, moreover, makes a very serious task of the deduction of the particular psychical functions from the original power, while Condillac takes it extraordinarily easy.  Good illustrations of his way of effacing distinctions instead of explaining them are given by such monotonously recurring phrases as memory is “nothing but” modified sensation; comparison and simultaneous attention to two ideas “are the same thing”; sensation “gradually becomes” comparison and judgment; reflection is “in its origin” attention itself; speech, thought, and the formation of general notions are “at bottom the same”; the passions are “only” various kinds of desire; understanding and will spring “from one root,” etc.

The demand for a single fundamental psychical power comes from Descartes, and Condillac does not hesitate to retain the word penser itself as a general designation for all mental functions.  Similarly he holds fast to the dualism between extension and sensation as reciprocally incompatible properties, opposes the soul as the “simple” subject of thought to “divisible” matter, and sees in the affections of the bodily organs merely