la Raison impuissante.’ Need for the common sense with which human nature is charged, illustrates the impotence of man's unomniscient understanding and limited share of the Divine Reason. Taking those words of Pascal, Reid puts emphasis on 'la nature'; Hamilton on 'impuissance.' But both are recognised by each: it is a difference of emphasis. Neither Hamilton nor Mansel excludes the conservative influence of 'la nature,' taken in its integrity, in the way Mr. Herbert Spencer does, when he rests philosophy only on the strongly emphasised part of Hamiltonian philosophy. In Hamilton the 'raison impuissante' is insisted on really in order to make room for 'la nature'; on the ground that the logical understanding, here 'la raison,' is too impotent to be able to disprove the genuine judgments of the Common Sense.
Brown's rebellion against Reid early in the century, in the interest of a universal physical causation or association, has its parallel in Ferrier's revolt, in the middle of the century, against the Hamiltonian Reid, in the interest of abstract metaphysics as opposed to uncriticised common sense. In the name of philosophy he excludes from philosophy all except necessary truths of abstract reason; neglecting, as beneath its regard, the world of change, in which Reid’s mixed and practical reason, or Common Sense, had been offered as final guide. The office of philosophy, according to Ferrier, is among the eternal truths, which alone can be absolutely demonstrated, and which relieve philosophy from 'the oversight of popular opinion and the errors of psychological science,' which had been unworthily dignified as the final test of truth. The natural beliefs of mankind, instead of being worshipped as divine, are banished in Ferrier's philosophy,
