From Memories, Dreams, Reflections, 1954:
"Freud
was able to interpret the dreams I was then having [on their trip to
the USA in 1909] only incompletely or not at all. They were dreams with
collective contents, containing, a great deal of symbolic material. One
in particular was important to me, for it led me for the first time to
the concept of the 'collective unconscious'... ."
"This
was the dream. I was in a house I did not know, which had two stories.
It was 'my house.' I found myself in the upper storey, where there was a
kind of salon furnished with fine old pieces in rococo style. On the
walls hung a number of precious old paintings. I wondered that this
should be my house, and thought, 'Not bad.' But then it occurred to me
that I did not know what the lower floor looked like. Descending the
stairs, I reached the ground floor. There everything was much older, and
I realized that this part of the house must date from about the
fifteenth or sixteenth century. The furnishings were medieval; the
floors were of red brick. Everywhere it was rather dark. I went from one
room to another, thinking, 'Now I really must explore the whole house.'
I came upon a heavy door, and opened it. Beyond it, I discovered a
stone stairway that led down into the cellar. Descending again, I found
myself in a beautifully vaulted room which looked exceedingly ancient.
Examining the walls, I discovered layers of brick among the ordinary
stone blocks, and chips of brick in the mortar. As soon as I saw this I
knew that the walls dated from Roman times. My interest by now was
intense. I looked more closely at the floor. It was of stone slabs, and
in one of these I discovered a ring. When I pulled it, the stone slab
lifted, and again I saw a stairway of narrow stone steps leading down
into the depths. These, too, I descended, and entered a low cave cut
into the rock. Thick dust lay on the floor, and in the dust were
scattered bones and broken pottery, like remains of a primitive culture.
I discovered two human skulls, obviously very old and half
disintegrated. Then I awoke."
"I
saw from this that he was completely helpless in dealing with certain
kinds of dreams and had to take refuge in his [Freud's] doctrine. I
realized that it was up to me to find out the real meaning of the dream.
It
was plain to me that the house represented a kind of image of the
psyche--that is to say, of my then state of consciousness, with hitherto
unconscious additions. Consciousness was represented by the salon. It
had an inhabited atmosphere, in spite of its antiquated style.
The
ground floor stood for the first level of the unconscious. The deeper I
went, the more alien and the darker the scene came. In the cave, I
discovered remains of a primitive culture, that is, the world of the
primitive man within myself--a world which can scarcely be reached or
illuminated by consciousness. The primitive psyche of man borders on the
life of the animal soul, just as the caves of prehistoric times were
usually inhabit by animals before men laid claim to them.
During
this period I became aware of how keenly I felt the difference between
Freud's intellectual attitude and mine. I had grown up in the intensely
historical atmosphere of Basel at the end of the nineteenth century, and
had acquired, thanks to reading the old philosophers, some knowledge of
the history of Psychology. When I thought about dreams and the contents
of the unconscious, I never did so without making historical
comparisons;... . I was especially familiar with the writers of the
eighteenth and early nineteenth century. Theirs was the world which had
formed the atmosphere of my first-storey salon. By contrast, I had the
impression that Freud's intellectual history began with Buchner,
Moleschott, Du Bois-Reymond, and Darwin."
"The
dream pointed out that there were further reaches to the state of
consciousness... : the long uninhabited ground floor in medieval style,
then the Roman cellar, and finally the prehistoric cave. These signified
past times and passed stages of consciousness.
Certain
questions had been much on my mind during the days preceding this
dream. They were: On what premises is Freudian psychology founded? [...]
What is the relationship of its almost exclusive personalism to general
historical assumptions? My dream was giving me the answer. It obviously
pointed to the foundations of cultural history--a history of successive
layers of consciousness. My dream thus constituted a kind of structural
diagram of the human psyche; it postulated something of an altogether
impersonal nature underlying that psyche. It 'clicked,' as the English
have it--and the dream became for me a guiding image... .
This was my first inkling of a collective a priori beneath the personal psyche."
"The
dream of the house had a curious effect upon me: it revived my old
interest in archaeology. After I had returned to Zurich I took up a book
on Babylonian excavations, and read various works on myths."
From Mind and Earth, 1931:
"Perhaps I may be allowed a comparison: it is as though we had to
describe and explain a building whose upper storey was erected in the
nineteenth century, the ground floor dates back to the sixteenth
century, and careful examination of the masonry reveals that it was
reconstructed from a tower built in the eleventh century. In the cellar
we come upon Roman foundations, and under the cellar a choked-up cave
with neo-lithic tools in the upper layer and remnants of fauna from the
same period in the lower layers. That would be the picture of our psychic
structure. We live on the upper storey and are only aware that the
lower storey is slightly old-fashioned. As to what lies beneath the
earth's surface, of that we remain totally unconscious.
This
is a lame analogy.. for in the psyche there is nothing that is just a
dead relic. Everything is alive, and our upper story, consciousness, is
continually influenced by its living and active foundations. Like the
building, it is sustained and supported by them."
And he returns again to this image in Religion and Psychology, 1940:
“Our modern attitude looks back arrogantly upon the mists of superstition
and of medieval or primitive credulity, entirely forgetting that we carry the
whole living past in the lower storeys of the skyscraper of rational
consciousness. Without the lower storeys our mind is suspended in mid-air. No
wonder it gets nervous. The true history of the mind is not preserved in
learned volumes but in the living psychic organism of every individual.”