168 GENERAL CONDITIONS OF SCIENTIFIC RESEARCH. 



conservation of matter and force, the correlation and equi- 

 valency of the various /orces, &c. ; also an acquaint- 

 ance with the chief principles of operation of the human 

 mind in observing, comparing, classifying, generalising, 

 inferring, &c., and in combining and arranging the evi- 

 dence. 1 



The experimental basis of discovery is not new. 

 'Leonardo da Vinci, about the year 1452, insisted upon 

 the necessity of the experimental and inductive method of, 

 inquiry, in order to obtain new scientific knowledge ; and 

 even ' Aristotle, and other ancient philosophers, not only 

 asserted that all our knowledge must begin from experience, 

 but also stated, in language much resembling the habitual 

 phraseology of the most modern school of philosophising, 

 that particular facts must be collected ; that from them 

 general principles must be obtained by induction ; and 

 these principles of the most general kind are axioms.'' 2 



CHAPTER XVI. 



THE POSITION OF MAN AS A DISCOVERER IN NATURE. 



MAN is a part of nature, and cannot escape from it ; he is 

 primarily its servant, and in accordance with the principle 

 of equality of action and reaction, he is secondarily its 

 master or guide ; and in order to be enabled to discover 

 new truths and direct nature, he must first obey Nature's 

 laws. In matters of new knowledge, it is of no use to be 

 frightened at the truth ; people who are ignorant of the 

 great laws of creative power are often alarmed at new 



1 For further information respecting this part of the subject, see 

 Chapters XIV. and XXXVI. 



2 Whewell, History of the Inductive Sciences, vol. iii. 3rd edit. p. 54. 



