18 SCIENCE PRIMERS. [NATURE AND 



Scientific experiment shows that, in floating, it displaces 

 its own weight of the water. 



Scientific reasoning differs from ordinary reason- 

 ing in just the same way as scientific observation and 

 experiment differ from ordinary observation and ex- 

 periment that is to say, it strives to be accurate ; 

 and it is just as hard to reason accurately as it is to 

 observe accurately. 



In scientific reasoning general rules are collected 

 from the observation of many particular cases ; and, 

 when these general rules are established, conclusions 

 are deduced from them, just as in every-day life. If 

 a boy says that " marbles are hard," he has drawn 

 a conclusion as to marbles in general from the 

 marbles he happens to have seen and felt, and has 

 reasoned in that mode which is technically termed 

 induction. If he declines to try to break a marble 

 with his teeth, it is because he consciously, or un- 

 consciously, performs the converse operation of de- 

 duction from the general rule " marbles are too hard 

 to break with one's teeth." 



You will learn more about the process of reasoning 

 when you study Logic, which treats of that subject in 

 full. At present, it is sufficient to know that the laws 

 of nature are the general rules respecting the be- 

 haviour of natural objects, which have been collected 

 from innumerable observations and experiments ; or, in 

 other words, that they are inductions from those 

 observations and experiments. The practical and 

 theoretical results of science are the products 

 of deductive reasoning from these general rules. 



Thus science and common sense are not opposed, 

 as people sometimes fancy them to be, but science is 



