L] THE SOIL OF THE FIELD. 31 



Greek, mathematics, scientific chemistry, can yet 

 become as far as his brain enables him a truly 

 scientific man. 



But how shall we learn science by mere common 

 sense ? 



First. Always try to explain the unknown by the 

 known. If you meet something which you have not 

 seen before, then think of the thing most like it which 

 you have seen before ; and try if that which you know 

 explains the one will not explain the other also. 

 Sometimes it will; sometimes it will not. But if it 

 will, no one has a right to ask you to try any other 

 explanation. 



Suppose, for instance, that you found a dead bird 

 on the top of a cathedral tower, and were asked how 

 you thought it had got there. You would say, " Of 

 course, it died up here." But if a friend said., " Not 

 so ; it dropped from a balloon, or from the clouds ; " 

 and told you the prettiest tale of how the bird came to 

 so strange an end, you would answer, "No, no; I must 

 reason from what I know. I know that birds haunt 

 the cathedral tower; I know that birds die; and 

 therefore, let your story be as pretty as it may, my 

 common sense bids me take the simplest explanation, 

 and say it died here." In saying that, you would be 

 talking scientifically. You would have made a fair and 

 sufficient induction (as it is called) from the facts about 

 birds' habits and birds' deaths which you know. 



But suppose that when you took the bird up you 

 found that it was neither a jackdaw, nor a sparrow, nor 

 a swallow, as you expected, but a humming-bird. 

 Then you would be adrift again. The fact of it being 

 a humming-bird would be a new fact which you had 



