The retreat of interest from reality may occur at any time and assume a pathological form. Whenever reality becomes formidable, interest at first becomes sharpened in normal individuals. If a man has to cross a street, he is alive to the dangers of traffic ; if he is confronted by an enemy who seeks to kill him, his powers of rapid extraversion, in the form of action, are increased. This is a biological contrivance. But at times reality may assume such a terrible aspect that this primary , and normal reaction is engulfed in a totally different condition. Instead of turning outwards in the attempt to overcome the difficulty, interest retreats.

What is the result of this retreat ? It can best be studied by examining that condition known as shell shock, for here we can see the effect of the excessive impact of reality on the individual. The onset of the symptoms may be sudden or gradual, but the picture these cases ultimately present in hospital is typical. They lie in bed in a state of helplessness. This helplessness is of varying de-gree. They may be paralysed, blind, deaf or dumb, and this loss of function does not depend on local injury. As often as not no kind of injury can be found. They are incapable of any kind of effort. They cannot concentrate their attention on anything. Their memory is clouded, often to an extreme degree. Frequently they cannot take any nourishment save in fluid form. Their emotions are uncontrolled. They are always fretful, and sometimes tearful. The condition may persist for many months. If an attempt is made to interest them in anything, a difficulty is experienced. They shun company, they dread to go out of their rooms; Their fear or anxiety fastens on the smallest things. For example, one patient, a well-grown man, was extremely upset by a bird which perched on a branch outside his window. He conceived the idea that many other birds might come and create a disturbance or do him some injury.

Now all this reminds us of childhood. We say, instinctively, that these people behave like little children. But when we say this we do not realize with sufficient clearness that this description is remarkably true. They are not only like little children, but some of them are like infants and some are even like infants unborn ; they are alive, but they cannot see, hear or speak. All those forms of interest that are associated with adult life have vanished, and in place of them we have interest expressing itself in the simplest forms of infancy. The force that reveals itself as interest has retreated down to levels that belong to the first years of human life. This process is called regression. The conception of regression belongs very intimately to Dr. Jung's views of the formation of the neurotic symptom. In contra-distinction to Freud, Dr. Jung looks for the combination of circumstances immediately responsible for the neurosis in the present moment. Reality suddenly becomes formidable, in that it presents a difficult problem that requires solution. The outcome may be a neurosis, and the symptom that characterises it is to be looked upon as a reanimation of a past attitude or activity, belonging to childhood or infancy, caused by regression.

Regression is never complete along all the paths through which interest has progressed. It may be complete in one and partial in others. The symbolism found in the dream in these cases may be significant. A patient who was suffering from shell shock and had made no progress for many weeks dreamed that he was half buried in the earth. The lower part of his body seemed to be merged with the earth. We can see in this a symbolical picture of his psychological condition, that is, of his partial return to the beginnings of life. The earth, here, is the symbol of source, or mother.

Any failure of adaptation causes some degree of regression. Between the insensibility of the undeveloped and the control of the individualized person there is an imaginative state met with in many people in which the problems of an abnormally reinforced reality bear very heavily on the psyche. Partial regression from civilized standards to more brutal planes may bring about a successful adjustment, and this we can call regressive adaptation. By becoming more of a brute, by allowing hatred and lust to animate him, a man may successfully endure certain aspects of life in the trenches. But there is another kind of adaptation possible, and that is one in which the experiences of war may awaken some new conception of the meaning of life, so that the man can endure patiently. This we may call progressive adaptation. In general, regressive adaptation is bad. It runs counter to the evolutionary plan. But regression, such as occurs in shell shock, belongs to another category. It is involuntary and therefore not so obviously a moral question, though it often seems to point to a lack in the power of conscious adaptation. It may be a reaction coming from the unconscious that has as its aim the ultimate good of the individual.

We must glance for a moment at the kind of dreams that shell-shock people experience. It would seem that in the initial stages of shock, where the onset is gradual, sleep becomes increasingly disturbed by dreams connected with battle incidents. At first these dreams are vivid reproductions of actual scenes that have occurred. Whatever the patient has seen, whatever horrible experiences he has undergone, and whatever things he has heard or imagined—and this in a much lesser degree— begin to appear as intensely emotional representstions in dreaming consciousness. During this phase regression is beginning and it becomes increasingly difficult for the victim to carry out his duties. A point is soon reached when he is sent into hospital; it may be after some sudden and violent experience, such as being buried alive by a shell; or it may be on the recommendation of his medical officer, who has noticed the gradual deterioration of the patient; or it may be because the patient himself realizes that he has lost the power of understanding written orders, or of remembering instructions. As long as the regression is acute, battle-dreams dominate the sleeping life. They may be so terrible that the patient seeks to keep himself awake at night at all costs. In these dreams the flashes of bombs, the bursting of shells, and the thudding of bullets are reproduced with extraordinary vividness. In the waking mind these experiences are avoided; they break into consciousness at intervals, but the whole set of the patients' feelings is to shut them out. If we regard the mass of experiences connected with war as the battle-complex, then we must look on the position of this complex as marginal rather than unconscious. Now the battle experiences were at the apical point of the patient's life, and as a result of shock we find them in the marginal psyche and in the conscious we have an infantile attitude towards life. As time goes on, the battle-complex tends to move into the unconscious while the infantile attitude tends to become more definite in certain particular directions. The complex appears in dreams more rarely, and there is a tendency for it to be diluted, as it were, with other forms of symbolism. We might almost say that while there is no assimilation of the battle-complex in consciousness, there is some assimilation in the unconscious. The nature of this assimilation reveals itself in dreams in symbolisms that are of value when the attempt is made to construct for the patient some new apical point of growth. For it is not only reality in the form of war that keeps up the regression, but it is a concentration of all those factors of reality that the patient finds difficult. In a sense, in order to recover, he has to retread the path of his own development, in much the same way as the embryo retreads the path of evolutionary development, in a recapitulated form. This may occur without help. Sometimes it does not occur, and in these cases, help must be given.

The assimilation of the battle-complex in consciousness may be regarded as an effort towards healing. The unconscious cannot, save in an indirect fashion, influence the conscious will, and therefore cannot bring about a reconstruction in consciousness of the adult attitudes. In one case the patient who had suffered from a regression neurosis for many months, and had remained in a helpless condition, experienced the following dream: " I was in a trench. My great toe, with the nail, had come off, and I was debating with another soldier whether I should put it on again. I felt that I ought to." This patient had formerly suffered from pure battledreams, but in the above example it is possible to see a considerable degree of assimilation of the battle-complex into a form of symbolism which apparently deals with some possibility of choice.

In regarding this dream we must remember that the will operates most definitely at the apical point, or growing tip, of life, and that the effect of shock is to cut off or introvert this terminal point or bud. The great toe, if cut off, severely cripples the individual, since the ball of the toe supports the weight of the body in walking. The dream compares the psychological condition of the patient to that of a man whose great toe has been cut off, but can be replaced at choice, and it suggests that it should be replaced.

The spectacle of regression is seen in advancing age. There is a zenith in every individual, and once this is past regression begins. From the psychological standpoint this zenith may come early or late. Whatever in the past has sufficient intensity to hold a man's thoughts and feelings continuously, may cause regression. Thus it comes about that some men may really experience their zenith as early as their university days. In after-life everything they do and say tends to lead back to that period. It seems fairly evident that people who find their right expression in life tend to remain younger, in a psychological sense, than those who fail to find it. Uncongenial work ages a man rapidly. Now the lack of proper expression means, from our point of view, an accumulation of potential interest in the unconscious, while right expression means that nascent material is constantly welling up from the deeper levels of the psyche to find free expression. The regression, then, that accompanies the advance of years may be connected with psychic tension in the unconscious. Whatsoever we leave unexpressed or unsolved in the course of life, we leave in the unconscious. We do hot consume our own smoke properly. We are therefore handicapped increasingly, and the turning-point of life may be hastened.