326 SCIENTIFIC THOUGHT. 



were occupied with the many researches indicated here. 

 But as the contents of the ' Principia ' became familiar 

 and intelligible to men of science, a large army of 

 workers, collected from all sides, had within the first 

 century after its publication accumulated a great mass of 

 is. research. It is the glory of the old French Academy of 

 Newton. Sciences, in spite of the opposition to Newton that ruled 

 there for some time, to have in all earnest taken up his 

 great bequest, and to have made such a summary possible 

 as was given by Laplace in the two works above re- 

 ferred to. To Laplace belongs also almost exclusively the 

 merit of having recognised the importance which attaches 

 in all human science to the existence of error, and of 

 having founded the theory of probability. The element 

 of error cannot be eliminated from our observations and 

 our reasonings : the only true scientific method is to- 

 measure and study it. 



The gravitation formula of Newton not only brought 

 precision and definiteness into scientific work in the three 

 directions mentioned above it not only produced strict 

 definitions of the fundamental notions of dynamics, pro- 

 moted accurate measurements of physical quantities, and 

 inaugurated a new literature in pure mathematics ; but it 

 had, as all other great generalisations have had since, a 

 very far-reaching influence on scientific thought in other 

 16. ways. There always have been, and always will be, 



Several -11.. i 



interests several distinct interests which induce men to study 



which 



promote nature. Some are driven to it by curiosity, or a pure 



science. J J ' 



love of nature. To those who belong to this class the 

 end of the study of nature is to describe and to portray 

 the objects which surround us, to see and know them 



