Pioneering and highly influential founder of psychoanalysis (1856–1939) whose theories revolutionized the understanding the human psyche. TLS in German, signed “Sigm,” one page, 6 x 9, personal letterhead, May 11, 1924. Freud writes to his nephew, Edward Bernays, the founder of “public relations,” based on Freud’s theories. Bernays was also responsible for the handling of Freud’s business deals in New York. In part (translated): “Also in May, I lent you 150 dollars, so that your mother’s assets with me are now 460 dollars. Thus, three further months are paid for. I would suggest that you send a larger amount of money here after these three months.... The case of Washington Coffee arrived undamaged on 30 IV. I very much approve of you deducting the price for that upcoming royalties. I didn’t expect the coffee to be so expensive, however, I received your book from Boni & Liveright. As a real American, I was very interested in it....” Bernays' public relations efforts helped popularize Freud's theories in the United States. Bernays also pioneered the PR industry's use of psychology and other social sciences to design public persuasion campaigns. In fine condition, with a central horizontal mailing fold and a few light creases. JSA/John Reznikoff Auction LOA and RRAuction COA.