218 THE LIMITATIONS OF SCIENCE 



of scientific histories is, however, their attitude toward 

 hypothesis. Such hypotheses are clearly subjective in 

 character and are to be criticised in accordance with 

 the same standards as a philosophical system of Plato 

 or Kant. Instead of this they are invariably treated as 

 if they dealt with phenomena verifiable by experi- 

 ment. 



In our histories of science a number of things about 

 scientific hypotheses might have been brought out. In 

 the first place, all of them rest on mechanical analogies 

 and attempt to make of the world, both inorganic and 

 organic, a vast machine whose parts grind out motions 

 which reveal themselves to us as heat, light, thought, 

 and whatever else we are cognizant of. That is, a 

 mechanical explanation of phenomena is considered to 

 be the simplest and most satisfactory one that can be 

 given. But we know there is no criterion which will 

 distinguish the truth between many rival mechanical 

 hypotheses. Thus the explanation of phenomena is 

 dependent on subjective interpretation, and is in the 

 end a matter of personal opinion. Nor does the recent 

 attempt to replace matter by electricity escape this 

 difficulty since the principles governing electrical 

 forces and energy are the same as those controlling 

 matter. The restrictions pointed out are still in force, 

 with the substitution of the word electricity for matter. 



It is also evident that, however logically a scientific 

 hypothesis may be developed, we can never say that 



