218 LAMARCK AND DARWIN 



which would permit of the greatest perfecting (that of the 

 Vertebrates), a plan very different from those which she has 

 been obliged to form as a preliminary to reaching it, 

 one understands that, among the multitude of animals, one 

 must necessarily come across not a single system of organi- 

 sation which has become progressively perfected, but diverse 

 very distinct systems, each of which has come into existence 

 at the moment when each primary organ first put in its 

 appearance" (p. 171). 



For Lamarck this order of Nature was not merely ideal 

 Nature had actually formed the classes successively, proceed- 

 ing from the simpler to the more complex ; she had brought 

 about this evolution by transforming the primitive species of 

 animals, raising them to higher degrees of organisation, and 

 modifying them in relation to the environment in which 

 they found themselves. 



Lamarck's theory of evolution is worked out in great 

 detail in his Philosophie zoologique^ but the exposition is 

 diffuse and disconnected ; it is better in giving an account of 

 it to follow the more concise, mature and general exposition 

 which he gives in the Introduction to his Histoirc natit relic 

 dcs Aiiiinan.v sans Vcrtebrcs^ Near the beginning of the 

 Introduction Lamarck gives us in a few short " Fundamental 

 Principles" the main lines of his general philosophy. He is 

 a confirmed materialist. Every fact and phenomenon is 

 essentially physical and owes its existence or production 

 entirely to material bodies or to relations between them. 

 All change and all movement is in the last resort due 

 to mechanical causes. Every fact or phenomenon observed 

 in a living body is at once a physical fact or phenomenon 

 and a product of organisation (p. 19). Life, thought and 

 sensation are not properties of matter, but result from 

 particular material combinations. 



His thorough-going materialism is most clearly shown in 

 its relation to living things in the first three of the " Zoological 

 Principles and Axioms," which are developed further on in 

 the book. 



These are as follows: " i. No kind or particle of matter 



1 Quotations in the text arc from the 2nd Edit. (Ueshayes and Milne- 

 Edwards), i., Paris, 1835. 



