There is no field in art, literature, or science in which the work of the critic is wholly superfluous. "There are periods in the growth of science," writes Professor Pearson in his deservedly popular work, "The Grammar of Science," [3] "when it is well to turn our attention from its imposing superstructure and to examine carefully its foundations. The present book is primarily intended as a criticism of the fundamental concepts of modern science, and as such finds its justification in the motto placed upon its title-page." The motto in question is a quotation from the French philosopher Cousin: "Criticism is the life of science." We have seen in Chapter XVI that a work on logic may be a comparatively simple thing. It may describe the ways in which men reason when they reason correctly, and may not go deep into metaphysical questions. On the other hand, it may be deeply metaphysical. When we approach the part of logic which deals with the principles and methods of the sciences, this difference is forced upon our attention. One may set forth the assumptions upon which a science rests, and may describe the methods of investigation employed, without going much below the plane of common thought. As a type of such works I may mention the useful treatise by Professor Jevons cited earlier in this chapter. On the other hand, our investigations may be more profound, and we may scrutinize the very foundations upon which a science rests. Both the other works referred to illustrate this method of procedure. For example, in "The Grammar of Science," we find our author discussing, under the title "The Facts of Science," such problems as the following: the Reality of Things; Sense-impressions and Consciousness; the Nature of Thought; the External Universe; Sensations as the Ultimate Source of the Materials of Knowledge; and the Futility of "Things-in-themselves." The philosophical character of such discussions does not need to be pointed out at length. [1] "The Principles Of Science," London, 1874, Preface. [2] English translation, New York, 1905. [3] Second edition, London, 1900. VI. ON THE STUDY OF PHILOSOPHY CHAPTER XXII THE VALUE OF THE STUDY OF PHILOSOPHY 80. THE QUESTION OF PRACTICAL UTILITY.--Why should men study philosophy? The question is a natural one, for man is a rational being, and when the worth of a thing is not at once evident to him, he usually calls for proof of its worth. Our professional schools, with the exception of schools of theology, usually pay little attention to philosophical studies; but such studies occupy a strong position in our colleges, and a vast number of persons not students in the technical sense think it worth while to occupy themselves with them more or less. Wherever liberal studies are prosecuted they have their place, and it is an honored place. Is this as it should be?