In order to get some form of cognizance or some form of experience of sensations and ideas there must be some one organic consciousness that experiences or lives through the psychic events. Thoughts, feelings, ideas, images, and sensations are occurrences in some one psychic individuality, a psycho-biological or psycho-physiological organism, an organism which possesses the living synthetic unity of consciousness. From a purely psychological standpoint we may term this living organic unity of consciousness―a subject. I use the term "moment-consciousness," or simply "moment" to indicate this synthetic unity of consciousness which constitutes the characteristic of the subject having the synthesis of mental experiences. This holds true of all psychic life, from the very lowest representative of mental life to the very highest, such as the self-consciousness of man.

        The subject, or the unity of the psycho-physiological individuality cannot be represented by a series, whether temporal or spatial, as a series ceases to be a unity, or a synthesis. For a series of independent events remains a series, while the synthesis or unity of the series is a superadded event. A series of psychic events must exist in and for some psychic unity or individuality which stands for the organic unity of consciousness, or for the synthesis of consciousness, no matter what the type of consciousness is, low or high, animal or human. This synthetic unity of consciousness, no longer a series, is indicated by the term "moment" or "moment consciousness." There are various types of moment consciousness, according as there are various forms or types of synthesis.

        Psychic contents or states of consciousness are always found in connection with some individuality. That piece of bread lying yonder may awaken hundreds of mental states under different conditions and in various organizations. My friend sitting by my side sees it, so do I, and so does the child, so does the bird in the cage, so does the dog, and so possibly does the fly flitting around the table. The states awakened are no doubt different, but they are of a psychic character none the less. My friend and I may be conscious of the personal element along with it. We may think it in the form of ownership: "It is who thinks, who has the thought of the bread;" but this is only one of the many forms under which the perception or thought of the bread may appear. One thing, however, is essential to all the states, different as they may be in their content, and that is the fact that they belong to some one individuality which under certain special conditions may also be of the nature of a personality. The individuality may be of a high or of a very low type, it may be that of a man or it may be that of a fly, but it must be some one conscious being that synthetizes the psychic state. It is this one synthetizing consciousness that constitutes the essence of what we term "moment consciousness."

        The moment consciousness is the subject, the psycho-biological individuality requisite in all psychic activity. The psychic individuality cannot be regarded as a series of independent physical events. For it may be asked, for whom does that series exist and to whom is it presented? A synthetizing moment consciousness, both subject and content, is a fundamental assumption of psychology, just as space is that of geometry, and matter and force that of physics and chemistry. This necessity of assuming a synthetizing moment consciousness becomes clearly manifested in the highest form of psychic activity, such as self-consciousness. For if self-consciousness be reduced to a series, it may be pertinently asked with John Stuart Mill, "How can a series be aware of itself as a series?"

        A moment consciousness must not be considered as something apart from its content; it does not exist by itself; it exists wherever and whenever psychic states are synthetized; it is the synthetized psychic material; mere synthesis without material is meaningless. On the whole, we may say that the moment consciousness is like an organism, it forms a whole of many constituent parts.

        In the moment consciousness we find psychic material synthetized round one inmost central event which in its turn may have a central point. It reminds one strongly of the cell; although it branches out in all directions, it has always its inmost central point, its nucleus, nucleolus, and nucleolinus. While I am sitting here writing, I take in the many impressions coming to me: The sunshine pouring through the window, the table, the ticking of the clock, the chair, the bookcase, and many other things in the room; all of them are formed and synthetized into one, and as such they form a moment consciousness.

        They are not, however, indifferently grouped; their unity is an organized whole with a center, with a vital point, so to say. At the heart of the synthetized whole there is a central point, the grouping around which constitutes the individuality of the particular moment consciousness. In my own case, the central interesting point is the paper on which I write the sentence just formulated, and is the inmost point, the principal idea under discussion which forms the nucleolinus, so to say, of the whole moment consciousness. The most interesting or the most important experience forms the center of the moment. The same object which seemingly gives the same experience assumes different meanings and is therefore really quite a different experience, according to the moment consciousness in which the perception or knowledge of that object is synthetized. These presently experienced states, synthetized within the moment, form the matter, or what we may term the content of the moment consciousness. The moment of consciousness will change with the changes of the synthetized content. As an official, I am now in my office doing my work, and the different experiences form one whole, an association of experiences, systematized and synthetized into an organic unity. As a family man, I am at home enjoying the company of my wife, children, and friends, and once more the experiences are organized into the unity of a moment consciousness. Now I am climbing mountains and stand on the slippery edge of a precipice, now I enjoy a conversation with the child I love, now I take part in the excitement of the political arena, now I sit on the bench of the jury listening gravely to the cross-examination of witnesses in a murder case; all these are nuclei for the formation of different moments. All of these depend on the different central experiences that form the kernel for the moment consciousness.

        The central experience, round which all other experiences are grouped and synthetized, forms, so to say, the very essence of the given moment consciousness, and as long as this central experience remains unchanged in its position the new experiences are assimilated within the same moment consciousness. The moment consciousness, therefore, does not vary with the change of the content, if only the assimilating nucleus remains invariable. Should, however, the content vary so that the central experience is transposed and some other one occupies its place, then the moment consciousness itself is changed. In fact, we may have the content of the moment consciousness entirely unchanged; but if the central experience alone is displaced from its position, then the moment consciousness itself becomes changed in its nature. Thus, if as a traveller I climb the mountains chiefly for the sake of pleasure, and keep the scientific and aesthetic aspects in the background, the moment consciousness will be entirely different from the one where the scientific or aesthetic aspects are in the foreground, and all other considerations in the background. The moment consciousness, we may say, is entirely determined by the leading central experience.

        The content of the moment consciousness, however, is not confined to the presently experienced psychic states only; it embraces the past, it includes memory, that is, it synthetizes outlived moments. In my present capacity of physician and working in the office, I may also include the experiences as traveller, as juror, as teacher, as companion, and as lover, but still the tone of this particular moment consciousness is given by the duties of my present occupation. The most vivid, interesting, and leading experiences form in this synthesis the nucleus round which all other experiences are crystallized and synthetized into one organic whole. We have here a series of moments, all of them being coordinated and contained in one synthesis of one moment consciousness.

        The members of this synthetized series are not of equal value nor are they qualitatively the same. The leading experience that constitutes the assimilating element of the given moment has reality, interest, and value, while others are only so much material support for the principal central experience. This central experience differs also from the other experiences synthetized in the moment consciousness by the fact that it alone, that is, the nucleus only, has the most vivid psychic states, sensational and perceptual elements, while the others may totally lack them. Other subsidiary synthetized moments are rather of an ideational character they are what is called "reproductions," ideal representatives of formerly experienced, outlived moments.

         The moment consciousness may contain moments that happened to emerge by the dynamic process of association, such as contiguity, similarity, or contrast. Each moment consciousness may become content for the next. Each successive moment consciousness may synthetize the preceding ones, contain them in an abridged ideational form, and may, moreover, recognize and claim them as belonging to itself, and as being one with them. There may, in short, be various forms of mental unification, but one thing stands out clear and that is the nature of the moment consciousness. The essence of the moment consciousness is mental synthesis.

         If we take a cross section of the moment consciousness, and try to fixate it with our mental eye, we find a central psychic element round which other psychic elements are crystallized. This central psychic element is prominent, vivid, forms, so to say, the vital point of all the states and gives the tone to the rest, forming a whole, one organized experience. The psychic matter that surrounds the luminous central point does not stand in a free, more or less disconnected relation to the latter, it is intimately related to the centre, and cannot be separated without destroying the moment as a whole and even the life existence of each particular constituent. The whole moment seems to form an organic network in which the other elements take their place, according to a plan.

         The structure of the moment may in this respect be compared to that of the cell. In the cell we discriminate the nucleus round which the protoplasm is grouped. The protoplasm is connected with the nucleus by a network, a cytoreticulum. The destruction of the nucleus affects the protoplasm and the destruction of the protoplasm affects the nucleus. The two are intimately, organically interrelated by the common network, the general plan of their organization.

         A concrete example will perhaps best answer our purpose. Suppose the moment is perceptual and consists only of one percept. Now in the percept we find a central sensory element surrounded by other elements. This central element stands out prominently in the given psychic state, while the other elements are subordinate. Not that those elements are unimportant for the percept, on the contrary they are of the highest consequence and moment, they only lie outside the focus of the psychosis. Along with the focus those elements form one organized whole. The intensity of the psychic state proceeds from the periphery to the centre. The elements can as little be separated from the central element as the area of the circle from its centre. By removing the centre the circle will be destroyed and the centre will cease to be what it is. All the elements of the percept form one texture having the central sensory element as its nucleus. 

        Integrated as all those elements are they are not, however, of equal value and importance for the life existence of the whole. The central sensory element is of the utmost consequence, it is the vital point of the whole experience. While, the change or destruction of one or some of the subordinate elements may still leave the total moment unchanged, or but slightly modified, a change of the central sensory element or of the nucleus will profoundly modify all the other elements and their interrelation; and a destruction of the nucleus will destroy the total moment. Like their neuron counterparts, the moments may be regarded as being organized into groups, systems, communities and constellations, aggregates of greater and greater complexity.