Page:Ferrier's Works Volume 1 - Institutes of Metaphysic (1875 ed.).djvu/511

RhPROP. IX.———— system affected the mind, than of the way in which external objects affected the nervous system. It attempted, by invoking the casual relation, to explain the intercourse which subsists between the body and the mind. External objects were supposed to operate on the nervous system by the transmission of some kind of influence—the nervous system was supposed to carry on the process by the transmission of certain images or representations—and thus our knowledge of external things was supposed to be brought about. The representations alone came before the mind; the things by which they were caused remained occult and unknown.

6. The first important correction which this crude hypothesis sustained was at the hands of the French philosopher Des Cartes. The doctrine was, that things remotely, and the senses proximately, transmitted to the mind a knowledge of external objects. Des Cartes had an eye for the fallacy of that position. He saw that things and the senses could no more transmit cognitions to the mind than a man can transmit to a beggar a guinea which he has not got. Material things, including of course the organs of sense, have no knowledge to give to man; and therefore man cannot receive his knowledge from material things; in other words, matter cannot be the efficient cause of our perceptions. The explaining cause is not adequate to the