Reid, I suspect, could hardly recognise, in the stuffed figure thus put up by Ferrier to be knocked down, either the ‘common sense’ in which _he_ found the root of a human knowledge of the realities revealed in place and time throughout the long experience of man, or the ‘perception’ in which things external to the individual mind make their appearance ‘in part.’ The practical impassibility of disbelieving the existence of other living beings, of discarding memory as wholly delusion, of treating man as irresponsible, and our surroundings as chaotic or wholly uninterpretable, alike for science and in common life—these were alleged constituents of the common sense with which Reid concerned himself. They all lie outside the demonstrations of Ferrier, in which he unfolds his theory in forms of artistic beauty and easy grace, which make him the most picturesque figure in the succession of Scottish philosophers. Yet Brown and Ferrier in the end helped on the expansion of Reid. * * * * * Before Ferrier passed away in 1864, a revolution in the conception of the universe was in progress in Britain. The idea of continuous physical evolution of external nature and of man, promulgated biologically by Darwin, and by Mr. Herbert Spencer as the all-comprehensive generalised law of a universe that was supposed to be the outcome of unknowable Power, has become a popular creed within the last forty years. Simultaneously, methods of development akin to Hegel were introduced by Dr. Hutcheson Stirling in his _Secret of Hegel_, and afterwards in Glasgow by Dr. Caird, who adorned Reid’s chair for nearly thirty years—methods for making explicit latent Divine Reason as what explains and sustains the universe. Reid’s appeal in a practical temper, to the mixed and moral reason in man, as that with which man is inspired—an appeal widened and prolific of deeper questions in Hamilton—was still too cautious to attempt to formulate the mysteries of existence, in fully intelligible principles, which should remove the darkness around the ‘little light’ with which Reid was satisfied. He would have looked with distrust at the more ambitious intellectual constructions which seemed to be superseding the common sense of human nature, as the human response to the sceptic or agnostic, whose philosophical knowledge turned all knowledge into ignorance at the last. Reid was too human to be satisfied with merely physical generalisations of sequences and co-existences of phenomena, finally unintelligible, and therefore unworthy of trust; and he would have been too cautious to accept a network of abstract intellectual necessities, latent in the universe, as the last and best human account of nature and man as actually found in place and time. To rest satisfied with the evolutionary generalisation he would have regarded as involving the ‘common error of philosophers since the days of Plato,’ in confounding moral agency with physical causation. Of the