﻿CONSCIOl'SNESS AND PAIN 



knocked over with a mortal blow. Every or- 

 ganism, except when in a special state of re- 

 pose—for instance, during the hibernation of 

 some animals and the period of a plant's ex- 

 istence when enclosed in a seed— every organ- 

 ism of whatever grade of development is 

 possessed of sensitiveness of essentially the 

 same character as that of the simplest bit of 

 protoplasm revealed by the microscope. As 

 the organism rises in the scale of being, 

 irritability takes on a correspondingly varied 

 development. And it may be asserted that 

 the recoil when I accidentally press my hand 

 against a thorn is of the same essential 

 nature as that of an amoeba or slime-mold 

 when pierced with a sharp point: or that the 

 so-called instinct of the dog which urges him 

 to follow up the scent of a rabbit when hun- 

 gry, has its basis in the same fundamental 

 property of living matter as that which 

 causes the lively spores of the salmon-fungus 

 (Saprolegnm) to swim toward the spot from 

 which there is a slight emanation of decaying 

 fish, or the leaf-mildew to turn and grow 

 toward the breathing pore of a grape leaf, in- 

 to which it desires to enter and find a congen- 

 ial place of development, because it detects a 

 slight escape of vegetable acids from that di- 

 rection. 

 Irritabilitv in its various forms must, there- 



