The fact of consciousness is the great mystery of psychology. It is difficult even to define the term, although every person of average intelligence understands what is sought to be conveyed by it. Webster defines it as “knowledge of one’s own existence, sensations, mental operations, etc.; immediate knowledge or perception of any object, state, or sensation; being aware; being sensible of.” Another authority defines the term as “the state of being aware of one’s sensations; the power, faculty, or mental state of being aware of one’s own existence, condition at the moment, thoughts, feelings, and actions.” Halleck’s definition is: “That indefinable characteristic of mental states which causes us to be aware of them.”
It will be seen that the idea of “awareness” is the essence of the idea of consciousness. But, at the last, we are compelled to acknowledge that it is impossible to closely define consciousness, for it is something so entirely unique and different from anything else that we have no other terms at all synonymous to it. We can define it only in its own terms, as will be seen by reference to the definitions above given. And it is equally impossible to clearly account for its appearance and being. Huxley has well said: “How it is that anything so remarkable as a state of consciousness comes about by the result of irritating nervous tissue, is just as unaccountable as the appearance of the jinnee when Aladdin rubbed his lamp.” All that we can ever know regarding the nature of consciousness must be learned from turning the consciousness in ourselves back upon itself–by focusing consciousness upon its own mental operations by means of introspection. By turning inward the conscious gaze we may perceive the flow of the stream of thought from its rise from the subconscious regions of the mind to its final disappearance in the same region.
It is a common error to suppose that we are directly conscious of objects outside of ourselves. This is impossible, for there is no direct knowledge of such outside objects. We are conscious merely of our sensations of, or mental images of, the outside objects. All that it is possible for us to be directly conscious of are our own mental experiences or states. We cannot be directly conscious of anything outside of our own minds. We are not directly conscious of the tree which we _see_; we are directly conscious merely of the sensation of the nerves arising from the impact of the light waves carrying the image of the tree. We are not directly conscious of the tree when we touch it and perceive its character in that way; we are directly conscious merely of the sensation reported by the nerves in the finger tips which have come in contact with the tree. We are directly conscious even of our own bodies only in the same way. It is necessary for the mind to experience that of which it may become conscious. We are conscious only of (1) that which our mind is experiencing at this moment, or (2) that which it has experienced in the past, and which is being re-experienced this moment by the process of the memory, or which is being re-combined or re-arranged this moment by the imagination.
But it must not be thought that every mental state or mental fact is in the field of consciousness. This error has been exploded for many years. The fact is now recognized that the field of consciousness is a very narrow and limited one, and that the great field of mental activity lies outside of its narrow limits. Beyond and outside of the narrow field of consciousness lies the great subconscious storehouse of memory in which are stored the experiences of the past, to be drawn again into the field of consciousness by an effort of the will in the act of recollection, or by association in ordinary remembrance. In that great region, also, the mind manifests many of its activities and performs much of its work. In that great region are evolved the emotions and feelings which play such an important part in our lives, and which often manifest a vague disturbing unrest long before they rise to the plane of consciousness. In that great region are produced the ideas, feelings, and conceptions which arise to the plane of consciousness and manifest that which men call “genius.”
On the subconscious plane the imagination does much of its work, and startles its owner by presenting him with the accomplished result in the field of consciousness. In the subconscious field is performed that peculiar process of mental mastication, digestion, and assimilation with which all brain workers are familiar, and which absorbs the raw mental material given it, separates, digests, and assimilates it, and re-presents it to the conscious faculties sometime after as a transformed substance. It has been estimated that at least eighty-five per cent. of our mental activities are performed below or outside of the field of consciousness. The psychology of to-day is paying much attention to this formerly neglected great area or areas of the mind. The psychology of to-morrow will pay still greater attention to it.
The best of the modern authorities agree that in the great field of subconscious mentation is to be found the explanation of much that is unexplainable otherwise. In fact, it is probable that before long consciousness will be regarded as a mere _focusing of attention_ upon mental states, and the objects of consciousness merely as that portion of the contents of the mind in the field of mental vision created by such focusing.