IN THE LAST HALF-CENTURY. 



87 



modern views of motion and its causes, 

 except in so far as the conception of at- 

 tractive and repulsive forces may be re- 

 garded as the modified descendant of the 

 Aristotelian conception of forms. In fact, 

 it is hardly too much to say that the 

 essential and fundamental difference be- 

 tween ancient and modern physical sci- 

 ence lies in the ascertainment of the true 

 laws of statics and dynamics in the course 

 of the last three centuries ; and in the in- 

 vention of mathematical methods of deal- 

 ing with all the consequences of these 

 laws. The ultimate aim of modern physical 

 science is the deduction of the phenome- 

 na exhibited by material bodies from phy- 

 sico-mathematical first principles. Wheth- 

 er the human intellect is strong enough 

 to attain the goal set before it may be a 

 question, but thither will it surely strive. 



The third great scientific event of our (3) Evo- 

 time, the rehabilitation of the doctrine of 



