Sigmund Freud skriver til sin venn Wilhelm Fliess i Berlin (her gjengitt i engelsk oversettelse -- originalen er på tysk):
"My dear Wilhem,Your kind-heartedness is one of the reasons I love you. initially, it seemed to me that you had broken off contact because of my remarks about the mechanism of the symptoms distant from the nose, and I did not deem this improbable. Now you surprise me with a discussion that takes those ideas seriously!
You are right that I am overflowing with new ideas, theoretical ones as well. My theories on defense have made an important advance of which I shall give you an account next time.
Even the psychological construction behaves as if it would come together, which gives me immense pleasure. Reporting on it now would be like sending a six-month fetus of a girl to a ball. ...
I am feeling I to IIa. I need a lot of cocaine. Also, I have started smoking again, moderately, in the last two to three weeks, since the nasal conviction has become evident to me. I have not observed any ensuing disadvantage. If you again prohibit it, I must give it up again. But do consider whether you can do this if it is only intolerance and not etiology [!?].
I began it again because I constantly missed it (after fourteen months of abstinence) and because I must treat this psychic fellow  well or he won't work for me. I demand a great deal of him. The torment, most of the time, is superhuman."
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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