418 MENTAL FUNCTION 



its lifetime, yet if the child were to study botany or vegetal physiology a 

 week she might know more about blades of grass than the farmer would 

 learn in fifty years of raising and curing them. The farmer would have 

 acquired an enormous perceptual knowledge of blades of grass, and 

 the student some conceptual knowledge about blades of grass. For 

 almost every purpose the knowledge about is worth more than the 

 knowledge of. 



UNDERSTANDING can be described only in the same way as we have 

 suggested the fusion-process in conception. This indescribable multi- 

 tude of concepts which the human adult of average intelligence has some- 

 how stored in his brain combine and interact and develop what we call 

 the understanding of things. As the material of this marvellous process, 

 every man has concepts of a multitude of different kinds of objects rang- 

 ing from his collar-button to the sublimest notions of Ultimate Reality. 

 He has stored away in his nerve-paths concepts almost without end. 

 These in some way fuse together in his mind and brain and give him an 

 understanding of the facts and principles on which our human life is 

 conducted. (See also Expt. 88 in the Appendix.) 



THE REASON. A very perfect synonym of the term reason is the 

 expression common sense. It means more than a large store of varied 

 concepts, and much more even than understanding, for it indicates our 

 capability of so uniting the elements of the understanding as to produce 

 new aspects of things and to develop new truths about the relations of 

 objects. In no one of the human mental faculties do the mass of men 

 differ more than in their gifts of reason. Many have good understandings 

 of essential principles who seldom combine their energies in new ways so 

 as to produce new results. This reasoning process is the highest and 

 most advanced of the human mental functions. 



The physical basis of the understanding and the reason is to be sought 

 in the same process of neural fusion which we have seen everywhere 

 present in describing the stream of consciousness. The products of the 

 understanding, the multitude of concepts, and the percepts interact 

 to produce mental products which are entirely new, of large value in the 

 conduct of personal and social life and in the advancement of the world. 



The Relations of Body and Mind. We have now suggested in a very 

 brief and inadequate way some of the facts which can be observed on 

 introspection as to the stream of consciousness of any normal human 

 individual. As has been sufficiently emphasized, this stream is a process 

 and in no sense a substance. The other chapters of the book describe 

 in somewhat more detail the bodily processes, the stream of material 

 movements. These last are no more substantial than the others, although 

 they continually have reference to something that we call the body 

 which appears to us to be substantial. The mental process is a series 

 of movements in consciousness. The bodily process is no less a series 

 of movements in "matter." Our next inquiry very briefly refers to the 

 relations between these two series of movements which continue as long 

 as life endures. 'We shall keep as far as possible from the ultimate 



