216 FORCE HAS NO DETERMINING POWER. 



by the union of the property of chemical affinity and 

 the force of chemical attraction must always be traced 

 back to the inherent properties of the ultimate ele- 

 ments. Therefore, although force is essential to all the 

 physical and chemical states of aggregation and com- 

 bination known to us, it is incapable of being the 

 directive or formative cause of any of them. The 

 spherical form of small masses of fluid is not caused 

 by any " force of sphericity" forming them into that 

 shape, but simply results from the adhesive attraction 

 of the molecules overbalancing their weight ; and the 

 shape of a crystal is not from any formative power of 

 "a force of crystallization," but simply from the 

 attractions and polarities of the molecules depending 

 on their specific properties coming into play on a given 

 diminution of the repulsion of heat. And so on 

 through the world of variety of chemical compounds,. 

 in no case is mere force, or " that which is expended 

 in the production of motion," the determining cause of 

 any form, shape, or specific affinity.* I may conclude- 



* The foregoing views on the necessity of the radical distinction of 

 property and force being always kept in view, and the impossibility of 

 any directive power in mere force, were published in 1871. It is onlj 

 in biology that difficulties are apt to occur, and render such observa- 

 tions necessary ; accordingly the subject is seldom touched upon by 

 the mathematical physicists, but in July, 1872, Mr. James Croll wrote 

 a paper in the " Philosophical Magazine," entitled " What Determines 

 Molecular Motion ?" which has great interest for us here as bearing on- 

 the subject. Mr. Croll has since stated that he published similar views- 

 fifteen years ago, in his book on " Theism," which I have not seen : it 

 is now out of print. In answer to the above question, Mr. Croll en- 

 larges on the prevalent error of attributing everything to force, and 

 insists that far more depends on the determination of force than upon 

 its existence ; " and therefore, unless force be determined by force, the 

 most important element in physical causation is a something different 

 from force." This he reasons out, and concludes that " the action of 

 a force cannot be determined by a force, nor can motion be determined 



