true that community of object is one of the criteria of external reality, but it is certainly not true that the community of the object gives rise to the perception of externality. It may, on the contrary, be claimed, and possibly with far better reason, that it is the object's externality that gives rise to its community.
The child in its growth learns to discriminate between things and persons. Persons move, act, make adaptations, while things are moved, acted upon, adapted to; persons initiate movements, things do not; persons are prime movers and it is to them that one has to look up in the satisfaction of needs and in the acquisition and use of things. As against persons things are contrasted as impersonal. Gradually the child learns to include himself within the class of persons, his hopes, wishes and desires come in contact, as well as in conflict with those of other persons, and he learns more and more of inner life and activity with which he finally identifies all personality. Personality is more and more stripped of the thing aspect until the inner mental life, especially in its will aspect, remains as its sole characteristic. Persons are willers, and it is these wills which are of the utmost importance for the child to learn as the fulfillment of his will depends on them. He then learns to class himself within the category of willers; he himself is a willer. Impersonal things, falling outside and being contrasted with the class of willers, are conceived as independent of persons.
Moreover, while from the very nature of the case each willer bears to things a direct relation, his relation to other willers is only to be established through things. Wills come in contact not through the mere fact of willing, but through their relations to things. Coming in direct relation with things, things alone give direct experience, experience in its first intention. In other words, only things give rise to sensation or rather perception; hence sensory life with its time and space experience giving rise to externality is the criterion of the universe of things, conceived as independent of will. Only thing is external, will is not. Wills, however, can come in relation through things, and only through the same things; the universe of things must be a common one to all the wills, if these wills are to come into relation at all. In other words, the physical universe, genetically regarded, is external not because it is common, but it is common, because it is external.
The definition of the physical object as that which is common to many minds and of the psychic object as that which is present to one mind only is not acceptable, since it postulates the result of complicated epistemological reflection and psychological research, still very doubtful in themselves, at the very outset of the science of psychology. It may be that the world is nothing but consciousness and that the physical universe is nothing but the social object of many minds; still all this belongs to the domain of epistemology and metaphysics. The psychologist deals with phenomena and not with the "really existent." Standing on the ground of psychology the psychologist has no right to reduce the physical world to psychic terms; in fact, such a procedure would undermine his science, as all distinction between psychic and physical facts would become obliterated. For if by an "object" common to many minds we mean an object external to those minds, then we gain nothing at all by introducing the "many," it is just this "external" that has to be defined; if by the "common object" we mean an object psychic in its character, but only of a social nature, then we reduce the physical unLverse to consciousness and thus identify physical and psychic processes. Such identification is an obliteration of the opposition between the psychic and physical facts, an opposition with which the psychologist must set out, if he is to place psychology in the hierarchy of natural sciences. The psychologist must postulate the existence of an external physical world, just as the geometrician postulates space or the mechanician matter and motion.
It is the task of the epistemologist and metaphysician to inquire into the nature of that physical world whether it really exists independent of consciousness. Without, therefore, going into metaphysical considerations, I think it is best to define the physical phenomenon as the object or process conceived as being independent of consciousness, while the psychic object or process is one that is conceived as being directly dependent on consciousness. It seems to me that this definition has the merits of being positive as the one given by the representatives of the idealistic school; it has not the defects of bringing in irrelevant metaphysical and epistemological considerations; and it has furthermore the advantage of being fully in accord with the data and postulates of psychology.
IV Psychic States as Objects
The attacks may now be renewed from quite a different direction. We asserted that psychology deals with facts of objective, natural existence, the subject matter of science in general. How does it rhyme, it may be asked, with the conclusion just arrived at, namely, that the facts of psychology are different from those with which other natural sciences deal? To this may be answered that facts may agree in being objective, and still differ widely as to kind, a square and a man, a pound and a mile, are all objective, and still their difference is certainly a fundamental one.
An objection may be raised that may to some appear as a very grave one. Is psychology a science at all? Does it actually deal with objective natural existence? Physics, chemistry and other concrete sciences treat of objects, of facts, in the external world. Any one can go and verify those phenomena and their relations. This, however, is not the case with facts of consciousness, they are essentially subjective. Psychology, therefore, properly speaking, is not a science in the same sense as other sciences are. This objection may be easily obviated by the very simple consideration that the facts of any individual consciousness are as much objective to other people, as the chair, the table, the molecule, the atom. My individual consciousness is considered by others as external, as objective, as existing outside of their consciousness, and, in fact, were it not so, there would have been no individuality.
After this lengthy discussion we at last arrive at the conclusion, that although the facts which psychology treats of are not of a material, physical nature, they are none the less objective in character. Objective however, as the facts are, they are not independent of consciousness in the same way as the objects of the external world are regarded, they are essentially facts of consciousness.
"What is the relation," it may be asked, "of psychology to the physical and biological sciences?" The physical and biological sciences constitute a system of knowledge of the material world. Psychology investigates the genesis of this knowledge. Mechanics, for example, treats of motion and space. Psychology investigates not what motion and space are in themselves, but what the elementary acts of consciousness are out of which the space and time perceptions are developed.
The different objects which other sciences treat of may be regarded psychologically, and studied from the standpoint of their rise and development in consciousness. For objects to be known at all must first be perceived or conceived by consciousness. Psychology implies knowledge of the physical world as the content of consciousness. In order to know how perception and conception of objects originate, those objects must first of all be given. A thing that is not yet in existence cannot possibly be analyzed. It is only when knowledge of objects is already formed that one can begin to think about knowledge itself, how it originated and how it came to be in the shape possessed by the knowing mind. Physical sciences are in that relation independent of psychology, the former can be carried on to a high degree of perfection without any knowledge of psychology, while psychology without knowledge of the physical world would simply lack subject matter.
Apart, however, from the fact that psychology has as its subject matter the objects of physical sciences as perceived by and developed in consciousness, it also studies the forms, the character, the way of working of consciousness, it formulates the laws of how consciousness works, and analyzes into simplest elements and their combinations, the rich material that goes to make up the mental life of individual existence, or what is known as mind.
The postulated objective reality acts upon the given individual consciousness and gives rise to mental states which along with the objective representation of that reality has also its own coloring, its own subjective side.
The represented object floats so to say in a stream of consciousness. The subject matter which the psychologist