The missionary of a neglected truth is apt to be one-sided and even paradoxical, and strenuous expression was natural to Hamilton. From his first essay in 1829 to his last in 1855 he sought to show the inconsistency of infinite knowledge with our limited share of inspiration in the Common Sense. Accordingly, the negative and incomplete, or what Bacon calls ‘broken’ character of man’s knowledge, rather than its positive victories, is ever supreme in the _Hamiltonianised_ Reid, along with a recast of Reid’s account of the Common Sense as involved in perception of the outward things of sense. The respective offices of Reid and Hamilton might be compared in this aphorism of Pascal—‘_La Nature soutient 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.