The important bearing which this fact has upon this discussion is that it shows that unconscious processes are capable of memory, that is physiological memory. It may be said that this statement needs some modification if the sensory “impressions” guiding the decerebrate animal are to be interpreted as true psychological, however elementary, “sensations.” It would seem to me on the contrary only to accentuate the fact that the processes of the brainless animal are on a transition level between the purely unconscious processes of the spinal animal and the purely (if ever wholly so) conscious processes of the normal animal, and that intrinsically all are of the same nature. If sensation enters into the complex reflex reactions of the brainless animal it would seem that it can only be an elemental conscious factor in a complicated unconscious physiological mechanism. In this mechanism it can have no more specific importance in determining behavior, because of the fact of its being a psychological state, than if it were a receptor “impression” intercalated in the arc of an innate process. It is not linked with any associative memories of the past or foresight into the future; it does not constitute conscious intelligence. As a conscious experience it cannot have that kind of “meaning” which in the normal animal modifies instinctive processes and determines conduct. It probably plays simply the same part in the whole process, which otherwise is wholly unconscious, that the associative sensory image plays in determining the flow of thick or thin saliva in Pawlow’s dogs—simply a single link in a chain of associated reflex processes.
The next point to which I would direct attention is that from an objective point of view the behavior of the decerebrate animal may be in nature intelligent in the empirical sense of that word. The dog that growls and snaps when his foot is pinched, tries to draw it away, and, failing that, bites at the offending hand; the “educated” dog that jumps over a hurdle, and walks on his hind legs, following a stool supporting his front legs, to my way of thinking performs intelligent actions whether it has a brain or not. If intelligence is arbitrarily limited to actions performed by conscious processes, then intelligence becomes a mere question of terms.[[130]] There arises also the practical difficulty that certain types of behavior, which by common assent and common sense are regarded as purely automatic and unintelligent, must be termed intelligent because guided by consciousness. I cannot help thinking that “intelligence” is a pragmatic question, not a biological or psychological one. It would be much more conducive to a clear understanding of biological problems to use intelligence only as a convenient and useful expression, like sanity or insanity, to designate certain behavior which conforms to a type which, without strictly defining its limits, popular language has defined as intelligent. Sanity and insanity have ceased to be terms of scientific value because they cannot be defined in terms of specific mental conditions and much less in terms of mental processes. So intelligence cannot be defined in terms of conscious and unconscious processes. Any attempt to do so meets with insuperable difficulties and becomes “confusion worse confounded.” When we say then that the behavior of the decerebrate dog may be intelligent, all that is meant is that the animal exhibits behavior identical with that which in the normal animal we would empirically call intelligent. In this sense unconscious processes may exhibit intelligence. It was from this viewpoint, I think, that Foster concluded: “In short, the more we study the phenomena exhibited by animals possessing a part only of their brain, the closer we are pushed to the conclusion that no sharp line can be drawn between volition and lack of volition, or between the possession and absence of intelligence. Between the muscle-nerve preparation at one limit, and our conscious willing selves at the other, there is a continuous gradation without a break; we cannot fix on any linear barrier in the brain or in the general nervous system, and say ‘beyond this there is volition and intelligence, but up to this there is none.’”[[131]]
It has already been pointed out (Lecture V) that, in man, complicated actions which have been volitionally and perhaps laboriously acquired may be afterwards involuntarily and unconsciously performed.[[132]] In other words, after intelligent actions have been acquired by conscious processes, they may be performed by subconscious processes for which there is no conscious awareness and probably these may be either coconscious or entirely unconscious. There is no sharp dividing line between the activities of the unconscious, coconscious, and conscious.
When we descend in the scale of animal life to the insects (bees, ants, etc.,) we observe motor activity of a highly complex character of a kind that is termed intelligent, but we are forced to conclude, from various considerations, that the elements of consciousness have dwindled away to what can be nothing more than mere sensibility. In other words consciousness is reduced to its lowest terms, but behavior and the neural processes are maintained at a high level of complexity. Accordingly there is a disproportion between the complexity of the motor behavior and the inferred simplicity of consciousness, for in the higher animals the former would be correlated with complex psychological processes. If this be so, the motor activities must be determined by processes which are mostly unconscious.
In still lower forms of life the motor activities can be referred to simple tropisms, and thus necessarily are wholly unconscious.
Between the most complex unconscious physiological processes performed by the nervous system and the simpler cerebral processes accompanied by consciousness there is not as wide a step as might seem when superficially viewed. The physiological process may, as we have seen, manifest itself in acts of quite as intelligent a character as those exhibited by the conscious process, and indeed more so; for the conscious act may be little more than a limited reflex. On the other hand a psychological process may be so elementary that it contains nothing of awareness of self, of intelligence, or of volition in the true sense—nothing more, perhaps, than an elementary sensation without even perception. But it may be said that the presence of the most rudimentary state of consciousness makes all the difference and renders the gulf between the two impassable.
We are not called upon to discuss that question here. It is one which involves the ultimate nature of physical processes. A distinction should be made between psychological and psychical, these not being coextensive and always interchangeable terms. Psychological pertains to the empirical data of consciousness, (thoughts, ideas, sensations, etc.) while psychical pertains to the inner or ultimate nature of these data. Though the data as given in consciousness are psychical, that which is psychical may not be solely manifested as psychological phenomena. It may be manifested as physical phenomena and perhaps be identified with the energy of the universe. Hence the doctrine of panpsychism. And so it may be that in its ultimate analysis an unconscious process is psychical (monism) although not psychological and not manifesting itself as a datum of consciousness. Certain it is that, objectively viewed, there is nothing to distinguish physiological from psychological intelligence. If the extraordinary instinctive habits exhibited by insects, such as bees and ants and by still lower forms of animal life, can rightly be interpreted as, in large part at least, manifestations of physiological processes, as is quite possible, the distinction between the conscious and the unconscious in respect to intelligence and adaptability to environment would be reduced to one only of degree. That some of the lowest forms of life are endowed with consciousness, in any sense in which the word has psychological meaning, seems incredible, though they manifest instinctive intelligence of no mean order. The fact probably is, as I have just intimated, that those processes we call physiological and those we call psychological are in their inner nature identical, and the former are quite capable of functioning, incredible as it may seem, in a fashion that we are accustomed to believe can only be the attribute of conscious intelligence. This does not mean, of course, that the physiological intelligence can reach the same degree of perfection as that reached by conscious intelligence, though conversely, the latter may be of a lower order than physiological intelligence.[[133]] From this point of view we are logically entitled to regard physiological processes, even of the lower nervous centers and even though they are not acquired but due to congenital structural and functional arrangement, as phases of the unconscious.
Psycho-physical parallelism and monism.—According to the doctrine of psycho-physical parallelism every mental process is correlated with (accompanied by) a brain process. As brain processes thus viewed are “unconscious” (in the sense of not having the attribute of consciousness) we may express this in other terms and say: every “conscious” process is accompanied by an “unconscious” process. I have no intention of entering here into the question of the validity of the doctrine of psycho-physical parallelism. I wish merely to point out that if parallelism is a true formulation of the mind-brain problem, as I have just stated it, the converse ought to hold true, namely, that every brain process of a certain kind involving intelligence ought to be correlated with consciousness. But if some subconscious processes manifesting what is equivalent to thought, reasoning, judgment, imagination, volition, etc., are unconscious—as seems likely if not probable—then this converse does not hold true. This has some bearing on the validity of the doctrine; for if physical processes can perform substantially the same function as conscious intelligence it is difficult to reconcile this fact with what I may call naïve psycho-physical parallelism.
It is reconcilable, however, with psychic monism. According to this doctrine it is not a question of parallelism at all. There is only one process—the psychical. The physical brain process is only an aspect or special mode of apprehending this one. All is psychical but not psychological. That which we apprehend in the form of the unconscious is really psychical and hence is capable of performing the same kind of function as it performs when it becomes psychological. It is not at all certain that unconscious processes may not comprise an intelligence possessing faculties identical in kind with those of conscious intelligence and indistinguishable from the latter. Subconscious processes may exhibit perception, cognition, reason, imagination, conation (will), feeling, etc., and it is possible that some of these processes may be correctly interpreted as unconscious. At any rate, from the point of view of monism, whether the real psychical process or, probably more correctly, how much of it shall emerge as a psychological state of consciousness depends upon intrinsic conditions. Though we cannot penetrate within them it is quite conceivable that it is a matter of complexity of synthesization and coöperative activity of psychical energies. This is a most interesting problem closely related to that of awareness and self-consciousness.
The meanings of the unconscious, subconscious, and coconscious.—Though the term “unconscious” is in general use it has so many connotations derived from its various meanings in metaphysics, psychology, and physiology that its use has given rise to considerable confusion of thought, particularly, I am compelled to believe, in the interpretation of specific psycho-physiological phenomena. Nevertheless, it has been so well established in our nomenclature that we could not replace it if we would. Nor is it wholly desirable to do so. It is a good and useful term, but I believe that with each advance in the precision of our knowledge we ought, so far as accumulative data permit, to give precision to the concept for which it stands. Just as in physical science we attempt to give precision to our concept of electricity in conformity with new data accumulated from time to time, so our psychological concepts should be defined and limited in accordance with the advance in knowledge. Some do not like to define the term, not being quite willing to commit themselves unreservedly to the complete acceptance of the physiological theory of memory and to cut adrift from the metaphysical concept of a subliminal mind. If the psycho-physiological theory of memory, which is now generally accepted, is sound, we have one meaning of the unconscious which is a very definite concept, namely, the brain residua, physiological “dispositions” or neurograms in which the experiences of life are conserved. These terms become, therefore, synonyms for the unconscious. That, under certain conditions, the passive neurograms may, under stimulation, become active and function unconsciously (i.e., without corresponding psychological equivalents being introduced into the personal consciousness), need not invalidate the concept. We are then dealing with an unconscious and dynamic process. The effects of such functioning are simply the manifestations of the unconscious and may be recognized either in modifications of the stream of consciousness or in bodily disturbances. The term unconscious is an appropriate and descriptive term to characterize that which is devoid of the attributes of consciousness. This use of the term has been sanctioned by common usage.