OF NATURAL PHILOSOPHY. 21 



which were at one time the sources of innumerable 

 mistakes and controversies) ; some excessively com- 

 plex, as man, life, instinct. But, what is worst of 

 all, some, nay most, have two or three meanings; 

 sufficiently distinct from each other to make a pro- 

 position true in one sense and false in another, or 

 even false altogether; yet not distinct enough to 

 keep us from confounding them in the process by 

 which we arrived at it, or to enable us immediately 

 to recognise the fallacy when led to it by a train of 

 reasoning, each step of which we think we have 

 examined and approved. Surely those who thus 

 attach two senses to one word, or superadd a new 

 meaning to an old one, act as absurdly as colonists 

 who distribute themselves over the world, naming 

 every place they come to by the names of those 

 they have left, till all distinctions of geographical 

 nomenclature are confounded, and till we are unable 

 to decide whether an occurrence stated to have 

 happened at Windsor took place in Europe, Ame- 

 rica, or Australia.* 



(16.) It is, in fact, in this double or incomplete sense 

 of words that we must look for the origin of a very 

 large portion of the errors into which we fall. Now, 

 the study of the abstract sciences, such as arithmetic, 

 geometry, algebra, &c., while they afford scope for 

 the exercise of reasoning about objects that are, or, 

 at least, may be conceived to be, external to us ; 



* It were much to be wished that navigators would be more 

 cautious in laying themselves open to a similar censure. On 

 looking hastily over a map of the world we see three Melville 

 Islands, two King George's Sounds, and Cape Blancos innu- 

 merable. 



c 3 



