Finally, among the symptoms of possible physical origin, epileptoid attacks were described in two of our cases. This is chiefly of interest in that such phenomena are extremely rare in the benign psychoses. We believe that the mental symptoms summarized above constitute a specific psychotic type of reaction capable of appearing in any severity from mere lethargy and indifference to profound stupor. Since the prognosis is good, we feel obliged to classify this with the manic-depressive reactions. Further justification for this grouping is found in the occurrence of the stupor reaction as a phase in many manic-depressive psychoses. A patient may swing from mania to stupor as from mania to depression, and when the partial stupors are recognized as milder forms of the same process, it seems to be a frequent type of reaction. If stupor be a reaction type, its laws must be psychological. According to the view of modern psychopathology, the essence of insanity is regression with indolent thinking as opposed to progressive and energetic mentation. One can look on stupor as being a profound regression. Effort is abandoned (apathy and inactivity), while the ideational content expresses a desire for a retreat from the world in death. It is possible to think of this regression as a return to the mental habit of the suckling period, when spontaneous effort is at its minimum. This, too, is the time when petulance and tantrums are frequent expression of a wish to be left alone, which may account for the negativism as a consistent symptom of the same regressive progress. Just as we regress in sleep, to rise refreshed for a new day’s duties, so the stupor case often shows excessive energy in a hypomanic phase before complete normality is reached. This corresponds again to the age-old association of the ideas of death and rebirth which we see together so frequently in stupor. It is the psychology of wiping the slate clean for a fresh start. The development and symptoms of stupor furnish evidence in support of the hypothesis of this type of regression. Dissatisfaction of any kind is the setting in which the psychosis begins and the commonest precipitating factor is some reminder of death. That loss of energy appears with the stupor is evident from the inactivity and apathy, while the thinking disorder can be shown to be the result of the same loss. The different “levels” of the stupor reaction also conform to a theory of regression. First there is mere indifference and quietness; then appear false ideas when normality is so far abandoned as to mean a loss of the sense of reality; withdrawal of interest from the environment, with its consequent centering of self, leads to the next stage--that of the spoiled child reaction; then follows the exclusion of the world around in the dramatization of death; finally, in the deepest stupor, mentation is so far abandoned that we can gather no evidence of even this delusion being present.