THE PROBLEM OF CONSCIOUSNESS. 295 



organism, acts as a stimulus which causes an irritation; the irritation 

 produces a reaction. Within the ordinary range of the stimuli to which 

 an organism is subjected, the reaction is teleological, that is, it tends 

 to the benefit of the organism. A familiar illustration is the presence 

 of food in the stomach, which produces a stimulus, the reaction to which 

 is manifested by the secretion of the digestive fluid for the purpose of 

 digesting the food. An organism might conceivably be maintained 

 solely by this mechanism in cooperation with the physical laws which 

 govern all matter. Life in such an organism would be a succession of 

 teleological processes, essentially mechanical and regulated automatic- 

 ally by the organism. By far the majority of biologists regard plants 

 as essentially conforming to this type of life. Whether they absolutely 

 so conform we do not, of course, yet know. 



A sensation involves the interpolation of consciousness between the 

 stimulation and the reaction, and in consequence there is established 

 the possibility of a higher order of adjustment to the external world 

 than can be attained through the teleological reaction to a stimulus. 

 This possibility depends upon the fact that the intervention of con- 

 sciousness permits an adjustment in accordance not merely with the im- 

 mediate sensation, but also, and at the same time, in accordance with 

 earlier sensations. Thus, for example, the child sees an object, and its 

 reaction is to take hold of the object, which is hot and hurts the child. 

 Later the child sees the object again and its natural reaction is to take 

 hold of it again, but the child now reacts differently because its conscious- 

 ness utilizes the earlier as well as the present sensation; the previous 

 sensation is dislocated in time and fused with the present sensation 

 and a new reaction follows. No argument is necessary to establish 

 the obvious conclusion that an organism which has consciousness has 

 an immensely increased scope for its adjustments to the external con- 

 ditions; in other words, consciousness has a very high value for the 

 organism. It is unnecessary to dwell upon this conclusion, for it will 

 be admitted by every one, except perhaps those who start with the a 

 priori conviction that consciousness is an epiphenomenon. 



A sensation gives information concerning the external world. Per- 

 haps science has achieved nothing else which has clone so much to 

 clarify philosophy as the demonstration that the objective phenomena 

 are wholly unlike the subjective sensations. Light is a series of undu- 

 lations, but we do not perceive the undulation as such, but as red, 

 yellow and green, or as we say colors ; the colors give us available infor- 

 mation, and we use them as so many labels, and we learn that reactions 

 to these labels may be helpful or hurtful, and so we regulate our con- 

 duct. Objectively red, yellow and green do not exist. Similarly with 

 the vibrations of the air, certain of which cause the sensation of sound, 

 which is purely subjective. But the sound gives us information con- 



