Condillac, like Locke, started with the proposition that all our knowledge comes from experience. While, however, Locke had indicated two sources for this knowledge, sensation and reflection, the outer and the inner sense, Condillac referred reflection to sensation, and reduced the two sources to one. Reflection is, with him, only sensation; all intellectual occurrences, even the combination of ideas and volition, are to be regarded only as modified sensations. It is the chief problem and content of Condillac’s philosophizing to carry out this thought, and derive the different functions of the soul out of the sensations of the outer sense. He illustrates this thought by a statue, which has been made with a perfect internal organization like a man, but which possesses no ideas, and in which only gradually one sense after another awakens and fills the soul with impressions. In such a view man stands on the same footing as the brute, for all his knowledge and all his incentives to action he receives from sensation. Condillac consequently names men perfect animals, and brutes imperfect men. Still he revolts from affirming the materiality of the soul, and denying the existence of God. These ultimate consequences of sensualism were first drawn by others after him, as would naturally enough follow. As sensualism affirmed that truth or being could only be perceived through the sense, so we have only to reverse this proposition, and have the thesis of materialism, viz.: the sensible alone is, there is no other being but material being. SECTION XXXI. HELVETIUS. _Helvetius_ has exhibited the moral consequences of the sensualistic standpoint. While theoretical sensualism affirms that all our knowledge is determined by sensation, practical sensualism adds to this the analogous proposition that all our volition springs from the same source, and is regulated by the sensuous desire. Helvetius adopted it as the principle of morals to satisfy this sensuous desire.