INTRODUCTION. 



CHAPTER I. 

 THE MIND AND KNOWLEDGE : PRELIMINARY TRUTHS. 



i. NATURE OF MAN : His MENTAL FACULTIES : SENSES AND 

 INTELLECT. Since Logic deals with thought and thought is a 

 product of the mind, we cannot better approach our subject than 

 by taking a general glance at the nature of the mind and the 

 way in which it acquires knowledge. There is a special branch of 

 philosophy which investigates all our mental activities : it is called 

 Psychology. We will here take over from psychology, without 

 any detailed analysis or discussion, those of its conclusions which 

 will help to throw light upon the subject-matter of logic proper. 

 The mutual bearings of logic and psychology will be explained 

 further on (20). It is man himself, who, by his own thought, 

 furnishes the subject-matter of logic. Now man is a corporeal 

 being, existing in space and time like all other corporeal or material 

 things, and, like them too, endowed with many mechanical, physi 

 cal and chemical properties and powers ; but he is also animate or 

 living, i.e. organically constituted in his material structure, and 

 endowed with life in common with the things of the vegetable or 

 plant world ; and he is sentient also, capable of sense perceptions 

 and sense desires, in common with the beings of the animal world ; 

 finally, he is rational, that is to say, possessed of a characteristic 

 aptitude peculiar to himself and entitling him to a place apart in 

 God s visible creation, the faculty of reason or intelligence (46). 

 Such is man s composite nature ; and this nature is the remote 

 principle or source of all his activities, rational, sentient, vegetative, 

 and non-vital, all alike. 



The proximate principles or sources of his various activities are 

 called faculties. To what faculty do his acts of thought belong, 

 and by what features are we to recognize them ? Well, even the 



VOL. I. I 



