212 BRITISH PHYSICIANS. principle, the laws of which can be known only from the observation of the phenomena peculiar to living bodies ; and these phenomena themselves, according to the solidists, result from the agency of this principle upon the fibres, among which nature is supposed to have distributed it, for the purpose of animating them all with a certain portion of energy and activity. In this school CuUen ap- pears to have formed himself. He considers the human body as a combination of animated organs, regulated by the laws, not of inanimate matter, but of life, and superintended by an immaterial prin- ciple, acting wisely, but necessarily, for the gene- ral health, correcting deviations, and supplying deficiencies, not from a knowledge and a choice of the means, but through a pre-established relation between the changes produced, and the motions required for the restoration of health. This prin- ciple, in its various ramifications, governed every part of his theory of medicine. The action or the torpor of the extreme arteries chiefly influenced the motions which the living principle regulated. From the dictates of Boerhaave no appeal had hitherto been made j this innovation was, as usual, hailed by the young with admiration, and regarded by the advanced with distrust or dislike. The sys- tem of Cullen is combined with so much judgment that it fills the mind as one whole ; nothing seems wanting, and nothing redundant. He has amply succeeded, at all events, in accomplishing that which he professed to be his principal aim, the improvement of the judgment : this should be the principal aim of every method of teaching ; and when the judgment is once matured, the student