16 INTRODUCTION 



called a method. It is, in some respects, a sort of dictionary, in which we proceed 

 from the properties of things to discover their names ; being the reverse of ordinary dic- 

 tionaries, in which we proceed from the names to obtain a knowledge of the properties. 



When the method, however, is good, it does more than teach us names. If the sub- 

 divisions have not been established arbitrarily, but are based on the true fundamental 

 relations, — on the essential resemblances of beings, the method is the surest means of 

 reducing the properties of these beings to general rules, of expressing them in the 

 fewest words, and of stamping them on the memory. 



To render it such, an assiduous comparison of beings is employed, directed by the 

 principle of the subordination of characters, which is itself derived from that of the 

 conditions of existence. All the parts of a being having a mutual correlativeness, some 

 traits of conformation exclude others ; while some, on the contrary, necessitate others : 

 when, therefore, we perceive such or such traits in a being, we can calculate before- 

 hand those which co-exist in it, or those that are incompatible with them. The parts, 

 properties, or the traits of conformation, which have the greatest number of these 

 relations of incompatibility or of co-existence with others, or, in other words, that 

 exercise the most marked influence upon the whole of the being, are what are called 

 important characters, dominant characters ; the others are the subordinate characters, 

 all varying, however, in degree. 



This influence of characters is sometimes determined rationally, by considering 

 the nature of the organ : when this is impracticable, recourse must be had to simple 

 observation ; and a &ure means of recognizing the important characters, which is 

 derived from their own nature, is, that they are more constant ; and that in a long 

 series of different beings, approximated according to their degrees of similitude, these 

 characters are the last to vary. 



From their influence and from their constancy result equally the rule, which should 

 be preferred for distinguishing grand divisions, and in proportion as we descend to the 

 inferior subdivisions, we can also descend to subordinate and variable characters. 



There can only be one perfect method, which is the natural method. An arrangement 

 is thus named in which beings of the same genus are placed nearer to each other than 

 to those of all other genera ; the genera of the same order nearer than to those of 

 other orders, and so in succession. This method is the ideal to which Natural History 

 should tend ; for it is evident that, if we can attain it, we shall have the exact and 

 complete expression of all nature. In fact, each being is determined by its resem- 

 blance to others, and its differences from them ; and all these relations would be fully 

 given by the arrangement which we have indicated. In a word, the natural method would 

 be the whole science, and each step towards it tends to advance the science to perfection. 



Life being the most important of all the properties of beings, and the highest of all 

 characters, it is not surprising that it has been made in all ages the most general prin- 

 ciple of distinction ; and that natural beings have always been separated into two 

 immense divisions, the living and the inanimate. 



OF LIVING BEINGS, AND OF ORGANIZATION IN GENERAL. 



If, in order to obtain a just idea of the essence of life, we consider it in those beings 

 in which its effects are the most simple, we readily perceive that it consists in the 



