INDUCTIVE AND DEDUCTIVE METHODS. 35 



for one's self. How slowly progress is made in the knowledge even of self- 

 evident matters, especially when respectable authorities disagree, I myself 

 have experienced sufficiently." K.AKL ERNST BAEK (1828). 



GUIDED by the fundamental law of Biogeny and by the 

 sure records of creation, we now turn to the interesting 

 tarfk of examining the animal parent-forms of the humait 

 race in their proper sequence. To ensure accuracy, we 

 must first become acquainted with the various mental 

 operations which we shall apply in this natural-philosophical 

 research. These operations are partly of an inductive, 

 partly of a deductive nature: partly conclusions from 

 numerous particular experiences to a general law ; partly 

 conclusions from this general law back to particular ex- 

 periences. 



Tribal history as a whole is an inductive science ; for 

 the whole theory of descent, as an indispensable and most 

 essential part of the whole theory of evolution, is entirely 

 founded on inductions. From all the biological incidents in 

 plant life, in animal life, and in human life, we have derived 

 the certain inductive conception that the whole of the or- 

 ganic inhabitants of our globe originated in accordance with 

 one single law of evolution. To this law of evolution, La- 

 marck, Darwin, and their successors gave definite form in 

 the theory of descent. All the interesting phenomena ex- 

 hibited by Ontogeny, Palaeontology, Comparative Anatomy, 

 Dysteleology, Chorology, the (Ekology of organisms, all the 

 important general laws, which we infer from multitudinous 

 phenomena of these different sciences, and which are most 

 intimately connected together, are the broad inductive 

 data from which is drawn the most extensive inductive 

 law of Biology, Because the innate connection between all 



