20 INTRODUCTION. 



experienced. We trace to without the cause of that sensation, and thus 

 acquire the idea oi the object that has produced it. By a necessary law 

 of our intelligence, all ideas of material objects are in time and space. 



The modifications experienced by the medullary masses leave impres- 

 sions there which are reproduced, and thus recall to the mind images and 

 ideas; this is memory — a corporeal faculty that varies greatly, according to 

 the age and health of the animal. 



Similar ideas, or such as have been acquired at the same time, recall 

 each other ; this is the association of ideas. The order, extent, and quick- 

 ness of this association constitute the perfection of memory. 



Every object presents itself to the memory with all its qualities or with 

 all its accessary ideas. 



Intelligence has the power of separating these accessary ideas of objects, 

 and of combining those that are alike in several different objects under a 

 f/eneral idea; the object of which no where really exists, nor presents it- 

 self per se — this is abstraction. 



Every sensation being more or less agreeable or disagreeable, experience 

 and repeated essays soon shew what movements are required to procure the 

 one and avoid the other ; and with respect to this, the intelligence abstracts 

 itself from the general rules to direct the ivill. 



An agreeable sensation being liable to consequences that are not so, and 

 vice versa, the subsequent sensations become associated with the idea of 

 the primitive one, and modify the general rules framed by intelligence — 

 tliis is prudence. 



From the application of these rules to general ideas, result certain for- 

 mulae, which are afterwards easily adapted to particular cases — this is called 

 reasoning. 



A lively remembrance of primitive and associated sensations, and of the 

 impressions of pleasure or pain that belong to them, constitutes imagination. 



One privileged being, man, has the faculty of associating his general 

 ideas with particular images more or less arbitrary, easily impressed upon 

 the memory, and which serve to recall the general ideas they represent. 

 These associated images are styled signs; their assemblage is a language. 

 When the language is composed of images that relate to the sense of hear- 

 ing, or of sounds, it is termed speech, and when relative to that of sight, 

 hieroglyphics. Writing is a suite of images that relates to the sense of 

 sight, by which we represent the elementary sounds, and by combining 

 them, all the images relative to the sense of hearing of which speech is 

 composed; it is therefore only a mediate representation of ideas. 



This faculty of representing general ideas by particular signs or images 

 associated with them, enables us to retain distinctly, and to remember 

 without embarrassment, an immense number; and furnishes to the rea- 



