40 The Relativitij of Knowledge. 



bound either to limit infinite nature to our finite concep- 

 tions, or to fly off at an insane tangent to the region of 

 fairies. We simply do not and cannot know, one way or 

 the other. For aught that we know to the contrary, the 

 heavenly bodies above may play the part of molecules in 

 forming worlds as much vaster than ours as it is larger 

 than a hydrogen molecule. In such colossal globes there 

 may be intelligent creatures of corresponding magnitude, 

 to whom our little world may be merely a tiny molecule. 



Again, downward amid our smallest specks of hydrogen, 

 may be complexities as great as those to which we are 

 accustomed. There may be beings and a civilization there. 

 No one can tell. If our world and all it contains, with all 

 visible things, should instantly expand from its present 

 size to that of a giant planet having globes of the precent 

 conceived size as its molecules, we could not know it. If 

 at the next instant it should shrink back again, and past 

 our present conceived point, to that of a hydrogen mole- 

 cule, we and all other things changing in perfect accord, 

 the alteration would be equally unknown to us. All our 

 relations remaining fixed, no method of experiment or in- 

 vestigation could tell of the change. Perhaps now, while 

 we speak, such a swing may be incessantly going on. We 

 know that, relative to one another, the sizes we bear are 

 the same as they were ten minutes ago ; but we do not 

 know whether in an absolute or infinite scale we have not 

 expanded or shrunk billions of miles in our dimensions. 

 We are in utter darkness upon the subject, and it is well 

 for us to know it. Ignorant conceit, only, shrinks from 

 such considerations. 



As we do not know whether we move at all or not, or, if 

 we do, in what direction we move, so we do not know what 

 size we absolutely bear, or whether we bear any constant 

 size at all. IMotion and size are meaningless terms outside 

 of mere relations. Turning to the weights of bodies, Ave 

 find ourselves forced to the similar conclusions, although 

 weight is our test of mass. The amount of substance in a 

 thing is supposed to be known by its weight. A grocer, 

 with what we call accurate scales, gives us a pound of but- 

 ter. Carried to the equator it is found to be less than a 

 pound. Carried to the pole it is found to be more tlian a 

 pound. Taken to the moon, it would require nine tinu^s as 

 much to make a pound. Taken to the sun, it would weigh 



