226 THE PRINCIPLES OF SCIENCE. 



The Newtonian Method, the True Organum. 



Laplace was of opinion that the Principia and the 

 Opticks of Newton furnished the best models then 

 available of the delicate art of experimental and theo 

 retical investigation. In these, as he says, we meet 

 with the most happy illustrations of the way in which, 

 from a series of inductions, we may rise to the causes of 

 phenomena, and thence descend again to all the resulting 



details. 



The popular notion concerning Newton s discoveries is 

 that in early life, while driven into the country by thej 

 Great Plague, a falling apple accidentally suggested to 

 him the existence of gravitation, and that, availing him- 

 self of this hint, he was led to the discovery of the law 

 of gravitation, the explanation of which constitutes the 

 Principia/ It is difficult to imagine a more ludicrous and 

 inadequate picture of Newton s labours and position. No 

 originality, or at least priority, could be or was claimed 

 by Newton as regards the discovery of the celebrated la^ 

 of the inverse square, so closely associated with his name. 

 In a well-known Scholium d he acknowledges that Sir 

 Christopher Wren, Dr. Hooke, and Dr. Halley, had 

 severally observed the accordance of Kepler s third law 

 of motion of the planets with the principle of the inverse 

 square. 



Newton s work was really that of developing the 

 methods of deductive reasoning and experimental verifica 

 tion, by which alone great hypotheses can be brought to 

 the touch-stone of fact. Archimedes was the greatest ol 

 ancient philosophers, for he showed how mathematical 

 theory could be wedded to physical experiments ; and hie 

 works are the first true Organum. Newton is the modern 



d Principia/ bk. I. Prop. iv. 



