350 NAT I RE AND MAN. 



XII. 

 THE FORCE BEHIND NATURE. 



[77;&amp;lt;? Modern Review, January, 1880.] 



SOME thirty years ago, I enjoyed opportunities of discussing with 

 John Stuart Mill (whose younger brother had been for twelve 

 months an inmate of my house) many questions of philosophy in 

 which we both felt the deepest interest Among these was the 

 Doctrine of Causation set forth in his recently published &quot; System 

 of Logic : &quot; &quot; We may define the cause of a phenomenon to be 

 &quot; the antecedent, or the concurrence of antecedents, on which it 

 &quot;is invariably and unconditionally consequent.&quot; I pointed out 

 to my friend that when this assemblage of antecedents is analyzed, 

 it is uniformly found resolvable into two categories, which may 

 be distinguished as the dynamical and the material ; the former 

 supplying the force or power to which the change must be attri 

 buted, whilst the latter affords the conditions under which that 

 power is exerted. Thus, I urged, when a man falls from a ladder 

 because (as is commonly said) of the breaking of the rung on 

 which his foot was resting, the real or dynamical cause of his fall 

 is the force of gravity, or attraction of the earth, which pulls him 

 to the ground when his foot is no longer supported ; the loss of 

 support being only the material condition or collocation, which 

 allowed the force previously acting as pressure on the rung, to 

 produce the downward motion of the man who stood upon it. 



To this Mr. Mill s reply was, that the distinction is one of 

 metaphysics, not of logic. I ventured, however, to press on him 

 that to whichever department of philosophy this point is to be 

 referred, is is one of fundamental importance ; that, assuming 



