ESSAY III.
SCOTTISH METAPHYSICS: THEORY OF CAUSATION.
It seems a common opinion that there is little connexion between the subtle reasonings of recluse thinkers, devoted to abstract speculation, and the actions, or even the discoveries which are important to mankind. Books of Metaphysics are thus cast aside as void of human interest. The philosopher, notwithstanding, pursues his vocation, without expecting to convert the multitude to his manner of life. In each generation we find meditative minds, struggling to obtain the most comprehensive survey of the boundaries of knowledge, the deepest insight of the foundation of human beliefs, and the truest interpretation of the life of man. And when we look beneath the "show of things" into the great heart of literature and social life, we find also that the intellectual agitation of these recluses has not really been unconnected, as it seemed to be, with the pulsations of that heart; that, on the contrary, those who have main-
