PRIMARY CONCEPTS OF MODERN SCIENCE. 359 



cience of a giddy metaphysician. One of the urgent needs of modern 

 physical science is a thorough investigation of the nature, methods, 

 and aids of scientific cognition, and thus of the nature of its real lim- 

 its, chiefly in the light of the teachings of comparative philology 

 and comparative psychology. Max Mliller has happily designated the 

 tendency to "reify" intellectual concepts (or, as Mill expresses it in 

 nominalist phrase, to mistake names for things), as " modern mythol- 

 ogy." But this mythology is not at all confined to ordinary lan- 

 guage ; it extends to all the formularies, including those employed in 

 scientific research, which serve as the intellectual net-work for the 

 delineation of physical phenomena and for the exact mathematical 

 determination of the laws of their interdependence. 



The most pressing need of modern physical science, however, is 

 the disengagement of the facts of observation and induction from 

 their present theoretical complications. Most of the scientific theories 

 of our day have their root in the metaphysics of three centuries ago, 

 and some of the materialistic speculations based upon them are redo- 

 lent of the ancient culture of the Middle Kingdom. Both in physics 

 and in chemistry (not to speak of the biological sciences), the facts 

 have long since transcended the narrow bounds of the prevailing sci- 

 entific hypotheses, and have thus been either ignored or misinter- 

 preted. On the remaining pages of this paper I desire to direct atten- 

 tion to some of the facts connected with the main subject of my pres- 

 ent inquiry — the concept force. 



Physical forces are distributed by modern science into two classes, 

 molecular and molar forces. Molecular forces are those which deter- 

 mine the internal changes of a body, while molar forces cause the mo- 

 tion of the entire mass. Molecular forces, therefore, are the agencies 

 which determine the particular state of the body in its physical rela- 

 tions, considering it as an independent whole — or, as it is termed in 

 modern mechanics, as an independent conservative system — while the 

 molar forces determine the physical relations of the body to other 

 bodies which, together with it, are integrant parts of a greater whole, 

 i e., of a more comprehensive conservative system. 



Modern science teaches that all physical forces, molar as well as 

 molecular, are mutually convertible. This fact is discussed and illus- 

 trated in scientific treatises without number, and its importance is 

 duly appreciated. But there is another fact connected with it, 

 equally well known, the significance of which is not, I think, at all 

 realized : all force in its physical origin is molecular. The power 

 which grinds the wheat in the mill on the stream, or which drives the 

 steam-engines in a factory ; the force which propels the cannon-ball 

 on its path of destruction, or the vital juices in a vegetable or animal 

 organism in their course of vital regeneration; the energy which 

 causes the muscles of a man's arm or the vessels of his circulatory 

 system to expand and contract — all are alike of helio-planetary origin, 



