94 SCIENCE PRIMERS. 



certain material phenomena and certain mental phe- 

 nomena. Thus, for example, certain sensations are 

 always produced by the influence of particular material 

 bodies on our organs of sense. The prick of a pin 

 gives pain, feathers feel soft, chalk looks white, and so 

 on. The study of mental phenomena, of the order 

 in which they succeed one another, and of the rela- 

 tions of cause and effect which obtain between them 

 and material phenomena, is the province of the 

 science of Psychology. 



All the phenomena of nature are either material 

 or immaterial, physical or mental; and there is no 

 science, except such as consists in the know-ledge 

 of one or other of these groups of natural objects, 

 and of the relations which obtain between them. 



