THE FUNCTION OF CONSCIOUSNESS. 497 



the contractile protoplasm. The important point about 

 these movements in most animals is, that their direc- 

 tion directly subserves the attainment of some position 

 which is favorable for the procurement of relief from 

 some unpleasant sensation, or the acquisition of some 

 agreeable one, or both. We have the best reasons for 

 believing this to be true of the vast majority of animals, 

 because their structure is fundamentally like our own, 

 and the inference that the same is true of the lowest 

 forms of life is justifiable until it is proven to be mis 

 taken. 



Lamarck has attributed the movements of animals 

 to the necessity of satisfying their instincts, without 

 entering into the metaphysical questions which this 

 involves. I have regarded the question as a meta- 

 physical one by asserting that the necessary prelim- 

 inary to movement is " effort," referring to what are 

 called "voluntary' as distinguished from automatic 

 motions. 1 



Without special organs of movement, a great part of 

 the phenomena of kinetogenesis would have no exis- 

 tence, precisely as natural selection cannot act unless 

 the materials for selection (i. e. variations) are already 

 in existence. In explanation of the origin of organs 

 of movement we have the general ability of the primi- 

 tive animal, or protozoon, to project portions of its 

 body-substance as pseudopodia, which, in more spe- 

 cialized forms, become persistent and more or less 

 rigid, as flagella, cilia, etc. ; which are the first distinct 

 organs which subserve the transportation of the body 

 from place to place. The causes which lead to these 

 changes are as yet obscure, but that the use of these 



1 Proceeds, Am. Philos. Soc., 1871, p. 18. Origin of the Fittest, 1887, p. 194. 

 390 



