1 6 Wilde, Evolution of tJie Mental Faculties. 



driving a stake into the ground, effects as much as a 

 hammer weighing three pounds with a velocity — 12, for 

 in both cases the quantity of motion or the momentum 

 = 36." Now the experiments of Smeaton, Wollaston 

 and others have shown that the real effect in this case 

 would be 6x6- = 216 and 3x12- =432, or double the 

 depth of penetration for the higher velocity than that 

 arrived at by the German psychologist. His further com- 

 ments, however, on the quantity of motion in a body are 

 highly significant, as he states that "the same law lies at 

 the foundation of the theory of the lever and of the balance. 

 For here also the smaller mass on the longer arm of the 

 lever or bearer of the balance has a greater velocity in 

 falling ; and multiplied by this it may be equal to, or 

 greatly exceed, the quantity of -motion or the momentnin 

 of the greater mass at the shorter end of the lever." He 

 adds that " the substance of this doctrine has long ago 

 been expressed by Newton and Kant." 



We have thus another striking example of an acute 

 thinker applying, in common with Descartes and other 

 philosophers, the Romano-Chinese measure of the motion 

 of connected bodies to those moving by the free action of 

 gravity. 



Bewildered by the contradictions of natural phil- 

 osophers, Voltaire, Reid and other writers have professed 

 to see further into both sides of the controversy than those 

 actually engaged in it, and, with the least amount of trouble 

 to themselves, have made a show of superior wisdom by 

 declaring that the dispute was entirely verbal. The latest 

 instance of this easy method of dealing with the question 

 is to be seen in a recent exposition of the philosophy of 

 Leibnitz by the Hon. B. Russell (1900), wherein it is 

 declared (p. TJ^ that " this controversy seems to modern 

 mathematicians to be mere logomarchy." 



