NATURAL SELECTION 



The Origin of 



The question of the origin of sensation and of thought 

 can be but briefly discussed in this place, since it is a subject 

 wide enough to require a separate volume for its proper 

 treatment. No physiologist or philosopher has yet ventured 

 to propound an intelligible theory of how sensation may 

 possibly be a product of organisation; while many have 

 declared the passage from matter to mind to be inconceiv- 

 able. In his presidental address to the Physical Section of 

 the British Association at Norwich, in 1868, Professor Tyndall 

 expressed himself as follows : 



" The passage from the physics of the brain to the corre- 

 sponding facts of consciousness is unthinkable. Granted that 

 a definite thought and a definite molecular action in the brain 

 occur simultaneously, we do not possess the intellectual organ, 

 nor apparently any rudiment of the organ, which would 

 enable us to pass by a process of reasoning from the one 

 phenomenon to the other. They appear together, but we do 

 not know why. Were our minds and senses so expanded, 

 strengthened, and illuminated as to enable us to see and feel 

 the very molecules of the brain, were we capable of following 

 all their motions, all their groupings, all their electric dis- 

 charges, if such there be, and were we intimately acquainted 

 with the corresponding states of thought and feeling, we 

 should be as far as ever from the solution of the problem, 

 ' How are these physical processes connected with the facts of 

 consciousness ? ' The chasm between the two classes of 

 phenomena would still remain intellectually impassable." 



In his latest work (An Introduction to the Classification of 

 Animals), published in 1869, Professor Huxley unhesitatingly 



except in the same sense that the action of man or of any other intelligent 

 being is a first cause. In using such terms I wished to show plainly that I 

 contemplated the possibility that the development of the essentiaUy human 

 portions of man's structure and intellect may have been determined by the 

 directing influence of some higher intelligent beings, acting through natural 

 and universal laws. A belief of this nature may or may not have a founda- 

 tion, but it is an intelligible theory, and is not, in its nature, incapable of 

 proof ; and it rests on facts and arguments of an exactly similar kind to 

 those which would enable a sufficiently powerful intellect to deduce, 

 from the existence on the earth of cultivated plants and domestic animals, 

 the presence of some intelligent being of a higher nature than themselves. 



