Sigmund Freud skriver til sin venn Wilhelm Fliess i Berlin (her gjengitt i engelsk oversettelse -- originalen er på tysk):
"You know that I do not laugh at fantasies such as those about historical periods, and I do not because I see no reason for it. There is something to these ideas; it is the symbolic presentation of unknown realities with which they have something in common. I am now very satisfied with my two cases; another year or two and I can express the matter in formulas that can be told to everyone."
Freud, S., et al. (1985). The complete letters of Sigmund Freud to Wilhelm Fliess : 1887-1904. Cambridge, Mass, Belknap Press of Harvard University Press.
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