It was his intention in the Synthetic Philoso phy to develop a complete and articulated con ception of all cosmic phenomena, including those of mental and social principles. His qualifica tions for attempting so comprehensive a task were wide powers of generalization, profound ac quaintance with the facts of the various sciences, and a veritable genius for detecting the relations and connections of phenomena that escape the specialist. No philosopher has employed such a wealth of illustration and facts to explain his meaning or to prove his thesis. It is the clear ness of his thought, the force of his illustra tions, and the dependence of his views upon the facts and methods of the inductive sciences that have given him his power over all thinkers, except the technical and traditional philosophers. His attempt to systematize all knowledge in terms of modern science must always receive high credit among intelligent men.
The First Principles endeavors to define the fields of 'the unknowable and the knowable,' and the postulates with which the study of the know able must be pursued. The whole weakness of Spencer's system is shown in his discussion of the unknowable. The Absolute, Space, Time, Matter, Force, and Motion were all taken as un knowable. After telling us that all these are un knowable, he asserts that the most certain things in our conviction are the 'Absolute' and all the other fundamental data for the knowable. Be sides, after telling us that all explanation con sists in reference to the known, he says that all phenomena are explained as manifestations of the unknowable. Then, in the discussion of the knowable, Space. Time, flatter, Force, etc.. ap pear as known. Both the strength and weakness of his system are due to this equivocal import of the term knowledge. If Spencer had omitted all reference to the dogma of the unknowable and confined himself to a discussion of the know able. he would have avoided the controversy which has invited the distrust of his system. The postulates with which he conducted his speculations were, besides the existence of Space, Time, Matter, Motion, and Force, the assumption of the indestructibility of Matter, the continu ity of Motion, and the persistence of Force, which be regarded as an a priori truth, though also determinable inductively.
The whole system is an application of the idea of evolution to the universe, and more particu larly to organic life and its forms, and to po litical and social institutions. Spencer's con ception of this process did not go beyond 'Dar win's in its details, but it was apparently quite as original and certainly more comprehensive. besides involving philosophic conceptions of which Darwin was incapable. Spencer applied the materialistic formula to the explanation of all things, but protested that he was not a ma terialist. Even if he had expressed his doctrine, as he said he could as well have done, in terms of consciousness, it would not have modified the accusation against his materialism, as the ex pression of philosophy in terms of mental states does not insure one against all that materialism stood for. In order to adapt the conception to all forms of phenomena, he variously expressed the process as the passage from the simple to the complex, from the homogeneous to the hetero geneous, from indefinite homogeneity to definite heterogeneity, and so on. This description of the
process brought him into controversy with all those who like metaphysics, and gave him no credit with those who do not. It was at best a vague formula, which might be true or false ac cording to the definition of the terms and the statement of the facts; the phrase at least meant nothing more than the facts, and was not ex planatory. In his facts and illustrations, how ever, Spencer gives a clearer idea of his doctrine than in his abstract formulas intended to cover every type of phenomena in the organic and in organic kingdoms. These facts, he thinks, show a continuous order of things with historical con nections and relations which suggest a common origin from some ultimate indefinite form of force which he calls matter and motion. Darwin did not pretend to go beyond the extension of a few types in the organic world or to develop their genesis. lie was content to demonstrate the origin of species in the organic world and left unsolved and undiscussed the general origin of things—a much larger task. Spencer sought to make intelligible the process of evolution throughout the whole field of nature, and hence the importance of his formula about the 'con tinuous redistribution of matter and motion,' as embodying the whole system of changes and growths in the cosmos.
It was Spencer's antagonism to the doctrine of creationism that caused a complete misunder standing of what evolution really undertakes to accomplish. The theory of creation was equiv ocal. It assigned a cause for the origin of phenomena, and it was associated with the con ception of the miraculous and supernatural. Spencer denied the creational theory and adopted the gradual development of all things in its stead. But what he failed to recognize suffi ciently, though lie sees it at. times. is the fact that evolution is the history of origin, not the explanation of it. It determines the law, not the cause of genesis. All that Spencer and his co adjutors established is the fact that the origin of things was gradual instead of catastrophal. Creationism was so closely associated with the latter conception that the disproof of great breaks in nature carried with it the principle by which every change has to be explained. The transition from species to species may be gradual instead of catastrophal, but this fact does not eliminate the agency of causes, and it was cause that the creationistic theory sought and un fortunately made catastrophal. It was natural, therefore, when the evolutionists showed that the process was gradual, that creationism should suffer to the same extent, but after all the real conquest was in favor of law instead of caprice in the order of nature, so that if Spencer and the evolutionists had refused to conceive their problem in opposition to creationism, and had limited themselves to the conception of the his tory of genesis, they would have escaped con troversy with the metaphysicians on the one hand and with the theologians on the other.