DETERMINATION OF EFFECTS. 431 



prevent the effect of a cause ; the motion of the wheels of 

 a seven-day clock is as much due to the power imparted in 

 winding it up as is that of the wheel of one which is wound 

 up every twenty-four hours. It is, nevertheless, an inaccu- 

 rate practice to think or speak of remote causes or effects 

 as if they were immediate, indirect ones as if they were 

 direct, or partial ones as if they were entire ; and it really 

 involves untruthful or contradictory ideas. An acorn is 

 neither the immediate, direct, or entire cause of an oak, 

 nor a rill of a river ; nor is an idea, selected hy us during 

 our youth, and made the object of desire, the immediate, 

 direct, or entire cause of our subsequent success or failure 

 in life. A chain of mental phenomena, the first one of 

 which is set in motion by desire, often increases greatly 

 in magnitude and complexity as it proceeds, in conse- 

 quence of the co-operation of liberated forces ; and this 

 frequently happens with an idea intensified by means of 

 volition. 



Compound or concurrent effects are usually separately 

 detected and measured by separating the causes which 

 produce them. In many cases also, where the effects are 

 from any circumstances inseparable, they may also be 

 separately detected and measured by means of the dif- 

 ferent, further, or less immediate effects which they 

 themselves produce. But when neither of these plans of 

 different manipulation are possible, we must explain the 

 results by an indirect method by inference. 1 



Quantitative determinations help us greatly in dis- 

 covering the causes and effects of things ; and many causes 

 cannot be found without such assistance. In physical and 

 chemical research, we continually require to measure causes 

 and effects. No kind of effect can exist without at the 



1 See pages 352-354. 



