Those with a penchant for ideation in an nals will take greater satisfaction in the ex eriments of Hobhouse, since he finds varied !vidence of what he considers animal ideas.
As a last example of current methods of in vestigating ideational behavior, one devised by may be briefly described. It, too, is a )roblem method. As used for human subjects, apparatus consists of a series of 12 similar keys, any number of which maybe used n a given experiment. For lower animals, a series of boxes, each with an entrance door and in exit door, takes the place of the keys.
The animal's task is to select from any Troup of boxes whose entrance doors are open hat one which bears a particular spacial rela Lion to the remaining members of the group, he relation having been determined in advance the . experimenter. Thus, the right box might, in one series of observations, be defined as the middle one of the group. The animal would be rewarded when it entered the middle box by presentation of food and punished by confinement in a given box each time it chose incorrectly. It, therefore, tries to make only correct choices. This is possible only if it can perceive the relation of middleness and react to it positively. Problems varying in difficultness from the extremely simple and easy to those practically insoluble by human beings can be presented• by means of the multiple choice ap paratus. The method promises to be fruitful of important results in animal psychology, psychopathology, and to contribute abundantly to the materials of genetic psychology.
Animal psychology is an infant science, or part-science. It has tremendous advantage over human psychology in the greater controllability of its subjects, for lower animals can be used in experiments which are either extremely dif ficult or impracticable in the case of human subjects. So vigorous has the new science be come that its methods and results are pro foundly influencing the development of the general science of psychology and contribut ing abundantly to the advancement of genetic psychology. See GENETICS; COMPARATIVE PSY
CHOLOGY ; GENETIC PSYCHOLOGY ; PSYCHOLOGY.
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