In the foregoing exposition we have now learnt something of the dream
work; we must regard it as a quite special psychical process, which, so
far as we are aware, resembles nothing else. To the dream work has been
transferred that bewilderment which its product, the dream, has aroused
in us. In truth, the dream work is only the first recognition of a group
of psychical processes to which must be referred the origin of
hysterical symptoms, the ideas of morbid dread, obsession, and illusion.
Condensation, and especially displacement, are never-failing features in
these other processes. The regard for appearance remains, on the other
hand, peculiar to the dream work. If this explanation brings the dream
into line with the formation of psychical disease, it becomes the more
important to fathom the essential conditions of processes like dream
building. It will be probably a surprise to hear that neither the state
of sleep nor illness is among the indispensable conditions. A whole
number of phenomena of the everyday life of healthy persons,
forgetfulness, slips in speaking and in holding things, together with a
certain class of mistakes, are due to a psychical mechanism analogous to
that of the dream and the other members of this group.

Displacement is the core of the problem, and the most striking of all
the dream performances. A thorough investigation of the subject shows
that the essential condition of displacement is purely psychological; it
is in the nature of a motive. We get on the track by thrashing out
experiences which one cannot avoid in the analysis of dreams. I had to
break off the relations of my dream thoughts in the analysis of my dream
on p. 8 because I found some experiences which I do not wish strangers
to know, and which I could not relate without serious damage to
important considerations. I added, it would be no use were I to select
another instead of that particular dream; in every dream where the