Letter from Sigmund Freud to Josef Popper-Lynkeus, August 4, 1916

Hotel Bristol, Salzburg
August 4, 1916

My dear Sir

I received from you on the first of the month a consignment with which I felt very pleased and honored. I waited to see whether it would be followed by an explanatory letter, but since this did not arrive-one can't trust the mail nowadays-I don't want to

postpone thanking you any longer and asking how you came upon the little book by Straus.1

As a reader of the Vossische Zeitung I was already familiar with your beautiful, envy-arousing appreciation of your deceased friend, Mach.2 Owing to my narrower point of view I have unfortunately never been able to appreciate his work and had to consider his way of treating psychic phenomena as unpsychological. The physicist and psychology don't go together very well. I remember my surprise years ago when I discovered that you (as the only one) recognized that the distortion of dreams is the result of censorship (“Dreaming like Waking” in Lynkeus).3 The all but hundred-year-old dissertation by Dr. Heinrich Straus is indeed very remarkable. It contains several things with which a former friend of mine, W. Fliess of Berlin, used to be very much preoccupied. By his own observation the latter revived many of the assertions about the rhythm of vital phenomena, and added the considerable discovery that two such rhythms exist, a masculine one of 23 days and a feminine one of 28, and even after that friendship came to an end I retained some faith in this idea. Furthermore I was pleased to find in the little pamphlet remarks that touch my own sphere of interest-for instance, that human beings try to resume the embryonic position in sleep, the comparison between hibernation and the migration of birds for which the phylogenetic derivation can easily be produced.

With thanks and best wishes for your good health

Yours very sincerely
Sigm. Freud