This development has, in the sphere of systematic philosophy, reached its highest expression in the voluminous works produced through the latter half of the nineteenth century by Mr. Herbert Spencer, whose recent death seems to mark the close of the period we have under consideration. The metaphysical assumptions and ontological value of the system of Spencer, as he wished it to be understood and interpreted, have perhaps, though not unnaturally, been quite too much submerged in the more obvious expressions of its agnostic positivism. In its psychology, however, the assumption of "some underlying substance in contrast to all changing forms," distinguishes it from a pure positivism in a very radical way. But more especially in philosophy, the metaphysical postulate of a mysterious Unity of Force that somehow manages to reveal itself, and the law of its operations, to the developed cognition of the nineteenth century philosopher, however much it seems to involve the system in internal contradictions, certainly forbids that we should identify it with the positivism of Auguste Comte. In our judgment, however, it is in his ethical good sense and integrity of judgment,--a good sense and integrity which commits to ethics rather than to sociology the task of determining the highest type of human life,--and in basing the conditions for the prevalence and the development of the highest type of life upon ethical principles and upon the adherence to ethical ideas, that Herbert Spencer will be found most clearly entitled to a lasting honor. III. The third number of our difficult tasks is to summarize the principal results, to inventory the net profits, as it were, of the development of philosophy during the nineteenth century. This task is made the more difficult by the heterogeneous nature and as yet unclassified condition of the development. With the quickening and diversifying of all kinds and means of intercourse, there has come the breaking down of national schools and idiosyncrasies of method and of thought. In philosophy, Germany, France, Great Britain, and indeed, Italy, have come to intermingle their streams of influence; and from all these countries these streams have been flowing in upon America. In psychology, especially, as well as in all the other sciences, but also to some degree in philosophy, returning streams of influence from America have, during the last decade or two, been felt in Europe itself.