MENTAL SCIENCE, or PSYCHOLOGY is the science of the mind. The science of the mind is the Latin equivalent for the word, of Greek derivation, psychology. Both are concerned with what is called the spiritual, or non-material, part of the human personality.
The great advancement made, since Aristotle, in psychology is found in the laboratory. For the present purpose, it is fitting to refer to the apparatus of such a laboratory in the most general way. The instruments for research, and for measuring the methods and results of research, are numbered by the scores. Among the more important of them are the tambour, an instrument designed to record movements upon smoked surfaces; the plethysmograph, designed to record the changes in the volume of blood in the arm; the pneumograph, designed to record the breathing movements; and there are also similar instruments for recording movements of the head and of the fingers. In fact, the instruments of the psychological laboratory apply to all senses and to the entire intellectual operations.
Mental science, or psychology, whether connected or unconnected with the labora tory, is divided into several branches. Chief among them are what is known as genetic, structural, and functional psy chology.
Genetic psychology is concerned with the origin and development of the mind. The chief question in this branch is whether the differentiation in the mental processes is quantitative or whether it is qualitative. For instance, does the think ing or the consciousness of the dog differ in degree or in kind from the thinking or consciousness of man? Under this head also such questions as instinct, habit, and the rate of mental develop ment, are of primary importance.
A second branch of the subject is known as structural psychology, which refers to the mind as a force in and of itself; and functional psychology, a third branch, refers to the operation of this force. The two terms, structural and functional, have the same relation, ap plied to psychology, that they possess when applied to physiology or anatomy.
One of the most important applications of modern psychology refers to measure ments. These measurements are at once direct and indirect. Direct, they have close relationship to the laboratory, and, in particular, to the measurements of the reactions to light and to sound. In direct measurement still continues certain forces and conditions of the laboratory, but enlarges the tests unto the use, for instance, of the memory, unto the origin and progress of mental fatigue, and unto certain muscular movements. The element of attention, of association of ideas, of correlation of facts, represent a field in which measurements, both as causes and as results, fill important functions.
Psychology, as a branch of American education, is a development of the last fifty years. It has found its place in the high school and academy, as well as in the college and university. In the secondary schools, a science so complex has, and should have, an insignificant „place. In normal schools, as a part of the process of training teachers, it holds a significant relationship as is shown in the article on Pedagogy. The proper field for psychology, however, is in the college or university. This field is at first cultivated by simple courses, largely experimental. It continues in the ex perimental development, and, presently, takes up such questions as comparative psychology, mental development in the individual, and also animal behavior, important in itself and also impor tant in comparison with the mental development of man. In certain uni versities, the comparative element is made to apply to the evolution of differ ent races and of race, as well as of individuals. The psychology also of the primary elements of truth, beauty, morality, and religion, are considered. In the laboratory special emphasis is placed upon research. Research is used as a basis for work for advanced de grees, as well as for its own sake. It is recognized that the field for special in vestigation is as limitless and diverse as are the conditions of the human mind.