and to allow the suppressed impulses of the Ucs to achieve expression, thus again making possible the process of hallucinatory regression? I think not, for when the critical guardian goes to rest- and we have proof that his slumber is not profound- he takes care to close the gate to motility. No matter what impulses from the usually inhibited Ucs may bustle about the stage, there is no need to interfere with them; they remain harmless, because they are not in a position to set in motion the motor apparatus which alone can operate to produce any change in the outer world. Sleep guarantees the security of the fortress which has to be guarded. The state of affairs is less harmless when a displacement of energies is produced, not by the decline at night in the energy put forth by the critical censorship, but by the pathological enfeeblement of the latter, or the pathological reinforcement of the unconscious excitations, and this while the preconscious is cathected and the gates of motility are open. The guardian is then overpowered; the unconscious excitations subdue the Pcs, and from the Pcs they dominate our speech and action, or they enforce hallucinatory regressions, thus directing an apparatus not designed for them by virtue of the attraction exerted by perceptions on the distribution of our psychic energy. We call this condition psychosis.

We now find ourselves in the most favourable position for continuing the construction of our psychological scaffolding, which we left after inserting the two systems, Ucs and Pcs. However, we still have reason to give further consideration to the wish as the sole psychic motive-power in the dream. We have accepted the explanation that the reason why the dream is in every case a wish-fulfilment is that it is a function of the system Ucs, which knows no other aim than wish-fulfilment, and which has at its disposal no forces other than the wish-impulses. Now if we want to continue for a single moment longer to maintain our right to develop such far-reaching psychological speculations from the facts of dream-interpretation, we are in duty bound to show that they insert the dream into a context which can also embrace other psychic structures. If there exists a system of the Ucs- or something sufficiently analogous for the purposes of our discussion- the dream cannot be its sole manifestation; every dream may be a wish-fulfilment, but there must be other forms of abnormal wish-fulfilment as well as dreams. And in fact the theory of all psychoneurotic symptoms culminates in the one proposition that they, too, must be conceived as wish- fulfilments of the unconscious. * Our explanation makes the dream only the first member of a series of the greatest importance for the psychiatrist, the understanding of which means the solution of the purely psychological part of the psychiatric problem. *(2) But in other members of this group of wish- fulfilments- for example, in the hysterical symptoms- I know of one essential characteristic which I have so far failed to find in the dream. Thus, from the investigations often alluded to in this treatise, I know that the formation of an hysterical symptom needs a junction of both the currents of our psychic life. The symptom is not merely the expression of a realized unconscious wish; the latter must be joined by another wish from the preconscious, which is fulfilled by the same symptom; so that the symptom is at least doubly determined, once by each of the conflicting systems. Just as in dreams, there is no limit to further over- determination. The determination which does not derive from the Ucs is, as far as I can see, invariably a thought-stream of reaction against the unconscious wish; for example, a self- punishment. Hence I can say, quite generally, that an hysterical symptom originates only where two contrary wish- fulfilments, having their source in different psychic systems, are able to meet in a single expression. *(3) Examples would help us but little here, as nothing but a complete unveiling of the complications in question can carry conviction. I will therefore content myself with the bare assertion, and will cite one example, not because it proves anything, but simply as an illustration. The hysterical vomiting of a female patient proved, on the one hand, to be the fulfilment of an unconscious phantasy from the years of puberty- namely, the wish that she might be continually pregnant, and have a multitude of children; and this was subsequently supplemented by the wish that she might have them by as many fathers as possible. Against this immoderate wish there arose a powerful defensive reaction. But as by the vomiting the patient might have spoilt her figure and her beauty, so that she would no longer find favour in any man's eyes, the symptom was also in keeping with the punitive trend of thought, and so, being admissible on both sides, it was allowed to become a reality. This is the same way of acceding to a wish-fulfilment as the queen of the Parthians was pleased to adopt in the case of the triumvir Crassus. Believing that he had undertaken his campaign out of greed for gold, she caused molten gold to be poured into the throat of the corpse. "Here thou hast what thou hast longed for!"