Le feu ne manifesterait plus aucune des propriétés que nous lui connaissons: que serait-il? C’est ce que nous ne saurons jamais. C’est d’ailleurs peut-être un problème qui ne répugne pas seulement à la nature de notre esprit, mais à l’essence même des choses. Quand même en effet on supprimerait par le pensée tous les sujets sentants, il faudrait encore admettre que nul corps ne manifesterait ses propriétés autrement qu’en relation avec un sujet quelconque, et dans ce cas ses propriétés ne seraient encore que relatives: en sorte qu’il me paraît fort raisonnable d’admettre que les propriétés déterminées des corps n’existent pas indépendamment d’un sujet quelconque, et que quand on demande si les propriétés de la matiere sont telles que nous les percevons, il faudrait voir auparavant si elles sont en tant que déterminées, et dans quel sens il est vrai de dire qu’elles sont.”—Cours d’Histoire de la Philosophie Morale au 18me siècle, 8me leçon.
An attempt, indeed, has been made by Reid and others, to establish that although some of the properties we ascribe to objects exist only in our sensations, others exist in the things themselves, being such as can not possibly be copies of any impression upon the senses; and they ask, from what sensations our notions of extension and figure have been derived? The gauntlet thrown down by Reid was taken up by Brown, who, applying greater powers of analysis than had previously been applied to the notions of extension and figure, pointed out that the sensations from which those notions are derived, are sensations of touch, combined with sensations of a class previously too little adverted to by metaphysicians, those which have their seat in our muscular frame. His analysis, which was adopted and followed up by James Mill, has been further and greatly improved upon in Professor Bain’s profound work, The Senses and the Intellect, and in the chapters on “Perception” of a work of eminent analytic power, Mr. Herbert Spencer’s Principles of Psychology. On this point M. Cousin may again be cited in favor of the better doctrine. M.
Cousin recognizes, in opposition to Reid, the essential subjectivity of our conceptions of what are called the primary qualities of matter, as extension, solidity, etc., equally with those of color, heat, and the remainder of the so-called secondary qualities.—Cours, ut supra, 9me leçon.