96 KNOWLEDGE AXD OPIXlOy. 



or ascertained knowledge ; everybody capable of 

 understanding it admits its truth ; and those who 

 are incapahl'" of understanding it must take it on 

 trust from the report of others. So, again, to put 

 a somewhat higher instance, with the rotundity of 

 the world. We all believe the world is round. 

 Some of us can verify for ourselves the reasoning 

 by which it is shown to be round ; and some of us 

 cannot. But, whether we can or whether we can- 

 not, we are alike bound to accept it. The belief 

 is science ; it is ascertained knowledge, not matter 

 of opinion ; we cannot disbelieve it without plung- 

 ing ourselves at once into all sorts of ridiculous 

 mistakes. Every ship that sails from America to 

 Europe, to India, to New Zealand, to the Cape of 

 Good Hope, proceeds upon the assured assump- 

 tion that the world is round, .and would never get 

 to its destination if it proved to be flat, or square, 

 or egg-shaped, or irregular. Every kind of large 

 undertaking upon the earth's surface takes for 

 granted its rotundity, and succeeds only because 

 it is really round. If you accept science, you will 

 find yourself in the right at hast ; if you do not ac- 

 cept it, you will most assuredly find yourself in the 

 wrong. A Chinaman may refuse to believe that 

 London is in England, and confidently assert that 

 it is really in France ; and, iis long as he remains 

 in China, and has no practical dealings with 

 London, his error will not greatly matter. But, 



