Page:Freud - Selected papers on hysteria and other psychoneuroses.djvu/146

132 forms of defense here considered, and hence the three forms of disease to which this defense leads may be united in the same person. The simultaneous occurrence of phobias and hysterical symptom«, so frequently observed in praxis, really belongs to those moments which impede a pure separation of hysteria from other neuroses and urge the formation of the "mixed neuroses." To be sure the hallucinatory confusion is not frequently compatible with the continuation of hysteria and not as a rule with obsessions; but on the other hand it is not rare that a defense psychosis should episodically break through the course of a hysteria or mixed neurosis.

In conclusion I will mention in few words the subsidiary idea of which I have made use in this discussion of the defense neuroses. It is the idea that there is something to distinguish in all psychic functions (amount of affect, sum of excitement), that all qualities have a quantity though we have no means to measure the same—it is something that can be increased, diminished, displaced, and discharged, and that extends over the memory traces of the ideas perhaps like an electric charge over the surface of the body.

This hypothesis, which also underlies our theory of "ab-reaction" ("Preliminary Communication"), can be used in the same sense as the physicist uses the assumption of the current of electric fluid. It is preliminarily justified through its usefulness in the comprehension and elucidation of diverse psychic states.