Freud was 35 years old when Madam Blavatsky died in 1891, it is not known if Freud and Madam Blavatsky ever met, however it could be, maybe she gave a lecture in a big library or theater and Freud attended, then maybe he could have talked to her at the après cocktail party, Madam Blavatsky was known to travel all around Europe, America and Asia, I suppose she gave lectures too, besides séances, anyways to my knowledge Freud never wrote about her, moreover Freud was a foe of religion, occultism and spiritualism. He was to rational, maybe to sec scientific. In her 1877 book “Isis Unveiled” Madam Blavatsky did not mention Freud, how could she? Freud was only 21 then and a student, he was not yet famous. Maybe he read her books, studied her books, were on the best seller list of those days, could very well be. Moreover Carl Gustav Jung made Freud famous, by introducing and defending Freud’s theories in the academic society, it was not the other way around, Freud was until then regarded as an outcast, a freak, however seemed to have had some authority in a small circle of adepts.
OK Freud / Blavatsky thats a bummer.
However Jung was very influenced indirectly by Madam Blavatsky, through Theosophy and Madam Blavatsky’s secretary G.R.S. Mead, he was frequently in contact with Madam Blavatsky during her last 7 years, was before and after her death very prominent in the Theosophy order. Mead’s specialty were Neoplatonism (the “ONE” transcendent and supreme ‘entity’ from which everything emanates) Gnosticism (radical dualism = good and evil are equally strong, mitigated dualism = good is stronger but evil is faster) Hermeticism (all about the “Corpus Hermeticum” book from 2nd to 3rd Century A.D. The Hermetica are Egyptian-Greek wisdom texts, which are mostly presented as dialogues in which a teacher, generally identified as Hermes Trismegistus, enlightens a disciple. The texts form the basis of Hermeticism. They discuss the divine, the cosmos, mind, and nature. Some touch upon alchemy, astrology, and related concepts) This influence of Mead on Jung is well documented and testified by contemporary friends of Jung. Also documented is that Mead went several times to Küssnacht (Switzerland) to visit and stay the weekend and sometimes longer at Jung’s house, talking for day and nights on end, drinking, laughing and smoking. However I recall that Jung has written: “I heard about Madam Blavatsky, but I don’t know her.” cannot give reference of this, or it must be in his “Jung: Gesammelte Werke” in one of his letters. Gesammelte Werke is complete works, or there must ever have been 20 years ago a copy (which I ordered) in local Dutch libraries called “Jung: Complete Works” because I checked what Jung had said about Nostradamus, Jung explained and interpreted a very lengthy prophecy of him, more in order to illustrate medieval astrology, peculiar enough so did Madam Blavatsky but she explained one of the short Centuries poems of Nostradamus, of what she thought was about the Crimea war, which was then I think 20 years ago or so at date of her writing.
Funny is also that Madam Blavatsky in those days already was thinking in terms of depopulation!?
She could have invented the concept of collective consciousness before Jung (in the sources you will find a quote of her that she uses the term: “unite the broken links of the chain of time to form with them the mysterious, dream foundation of our collective consciousness.”)