ABSTRACT
The term instinct is still used somewhat loosely in popular and even in psychological literature. But recent investigations have cleared up certain ambiguities and misconceptions. It is now generally recognized that instincts are not absolutely invariable, nor unerring, nor always biologically useful, and there is a general tendency to explain them in biological terms as inherited modes of response to specific stimuli which have been handed down through racial heredity owing to their value in the struggle for existence. It is maintained that out of the random and sporadic acts which characterize the living protoplasm, certain acts which have proved useful have become established in the race and a basis has been provided for them in the hereditary structure. Accordingly we mean by the term instinctive activity to indicate certain more or less complicated trains of movement which are adapted to certain ends useful to the race, which are congenitally determined, and are independent of previous experience by the individual organism. So far there is general agreement, but difference of opinion still prevails as to the psychical processes involved in or accompanying these trains of movements. To make this point clear it is necessary to discuss the relation between instinct, reflex action, and intelligent action respectively.
