PSYCHOLOGY, the science of mental phenomena. Opinion is far from unani mous on many of the most important points of psychological doctrine, espe cially on such points as involve a philo sophical view of the nature of mind.
Thus, in the first place, we have the view that psychology deals with the facts of the conscious mind which, when knowing, feeling, or striving, is always conscious of itself as knowing, feel ing, or striving—i. e., is self-conscious. But it has many difficulties. We can hardly ascribe self-consciousness to the lower animals or to very young chil dren, and yet some kind of mental life clearly belongs to them; so that it would seem that mental life and self-conscious ness cannot be identified. Further, many psychologists (including Hamilton) are of opinion that there are mental phenom ena unaccompanied by self-consciousness even in mature human life.
In the second place, a materialistic view of mind is connected with the at tempt to make brain physiology play the part of a psychology. It is plain, how ever, that a sensation or a feeling of pleasure or pain is a fact of an entirely different order from a neural disturbance. The one may accompany or even cause the other (or both may be only different aspects of the same ultimate existence), but the characteristic nature of the men tal fact is not reached by the most thorough investigation of its physiolog ical conditions, while the latter are in many cases much more obscure than the phenomena they are adduced to explain.
In the third place, an attempt has been made (sometimes apart from any philo sophical hypothesis as to the nature of mind) to start with certain mental facts —called presentations, sensations, or feelings—regarded as ultimate or inde pendent, and to trace the laws and man ner of their combination and succession.
This method has been worked with excel lent result by the English Associationist psychologists. By a similar method, and by treating presentations as forces, Her bart and his followers have elaborated a mechanism of the mind and reduced psychology to mathematical form. The difficulty of this mode of conceiving mind is to explain how a series of sensations —on any interaction of presentations— can generate the consciousness of a self persisting through changing states; and even to give any meaning to sensation or presentation without regarding it as ex perienced by or presented to mind. On these grounds many psychologists, while Influenced by the scientific method of the Assoeiationists and of Herbart, hold that presentation or sensation is only con ceivable as belonging to a subject or mind. So far, mind must be assumed by the psychologist as implied in the experi ence of which he has to trace the develop ment. This subject, or mind as the con dition of experience, may be admitted to elude psychological observation.
Consult "Psychological Principles" Ward (1918) ; "Psychology of Peoples" Le Bon (1898) ; "The Mind and Its Ed ucation" Betts (1916) ; "Educational Psychology" (1913-1914).