AIMS, ETC., OF SCIENTIFIC THOUGHT. 93 



intelligible style, but, as it was composed while the doctor was absorbed 

 in his investigations, it is somewhat defective in classification and 

 condensation. This is to be regretted, yet it is quite a secondary 

 matter. Mr. Wallace deprecates its literary defects, but cordially 

 concedes its scientific importance. He says : " It is so full of curious 

 and novel facts and experiments, it contains so much excellent reason- 

 ing and acute criticism, and it opens up such new and astounding views 

 of the nature and origin of life, that one feels it ought to and might 

 have ranked with such standard works as the ' Origin of Species ' and 

 the ' Principles of Biology,' if equal care had been bestowed upon it 

 as a literary composition." 



< 



AIMS AND INSTRUMENTS OF SCIENTIFIC THOUGHT. 1 



By Professor W. KINGDOM CLIFFOED, 



OF UNIVERSITY COLLEGE, LONDON. 

 I. 



IT may have occurred (and very naturally, too, to such as have had 

 the curiostity to read the title of this lecture) that it must neces- 

 sarily be a very dry and difficult subject ; interesting to very few, intel- 

 ligible to still fewer, and, above all, utterly incapable of adequate treat- 

 ment within the limits of a discourse like this. It is quite true that a 

 complete setting forth of my subject would require a comprehensive 

 treatise on logic, with incidental discussion of the main questions of 

 metaphysics ; that it would deal with ideas demanding close study for 

 their apprehension, and investigations requiring a peculiar taste to 

 relish them. It is not my intention now to present you with such a 

 treatise. 



The British Association, like the world in general, contains three 

 classes of persons. In the first place, it contains scientific thinkers ; 

 that is to say, persons whose thoughts have very frequently the char- 

 acters which I shall presently describe. Secondly, it contains persons 

 who are engaged in work upon what are called scientific subjects, but 

 who in general do not, and are not expected to, think about these sub- 

 jects in a scientific manner. Lastly, it contains persons who suppose 

 that their Avork and their thoughts are unscientific, but who would 

 like to know something about the business of the other two classes 

 aforesaid. Now, to any one who, belonging to one of these classes, 

 considers either of the other two, it will be apparent that there is a 

 certain gulf between him and them ; that he does not quite understand 

 them, nor they him ; and that an opportunity for sympathy and com- 



1 A Lecture delivered before the members of the British Association, at Brighton, 

 August 19, 1872. 



