The author's abilities and work in this line are too well-known to need an introduction to the Princeton public. The chief endeavour of the work is to get back to the first principles of art as revealed in the way in which they manifest themselves in the conditions of mind as related to those of matter. The author rejects the method of historic criticism as unsatisfactory and vicious in aesthetics, showing that the higher arts do not conform to its fundamental dictum that all art is the expression of the age in which it appears, but, on the contrary, are always more or less traditional. The fact which has distinguished the greatest masters in art, as in philosophy and science, is that they have resisted the influences of traditionalism sufficiently to be moved as much by their own feeling and thinking as by those of others who have preceded them; as much, therefore, by that which results from a psychologic method as by that which follows the historic. In an age when the influence of the latter is so potent, we must emphasize again, as in every period when production is at its best, the importance of the former. An extended treatment is given the subject of beauty, whose various theories are stated and discussed, and from them is drawn a conclusion which meets the leading requirements of all. The prominent characteristics of beauty, as complexity, unity and variety, and its effects, both physiological and psychological, are treated fully. Throughout is emphasized the idea that the general effect produced by all art-forms is representative. To this term the author applies a more extended significance than has been done heretofore, denoting by it an effect, the presence or absence of which in any work determines the presence or absence of artistic excellence. The term can be applied to all art-forms, considered either as expressive of thought and feeling in the mind of the artist, or reproducing by way of imitation things heard or seen in the external world. All works of art must contain enough of the imitative element to represent the surroundings suggested. This is true even of music, the least imitative of the arts, and can be affirmed even more strongly of literature, painting, sculpture or architecture. The peculiarity of all art is, therefore, that it not only presents, but literally represents both the thoughts which it expresses and the form through which it expresses them. The volume closes with a short but interesting criticism from the pen of Professor J. Mark Baldwin on Professor Raymond's theory of beauty, confirming the essential agreement between the theory and the results of modern investigation in physiological psychology.