Note on the Madnesses of Crowds
Once I knew a women whom internet mountebank Eliezer Yudkowsky had convinced of the proposition that neither consciousness nor self identity existed.
She told me she did not exist.
She held that her viewpoint, perceptions, thoughts, habits, passion, volition, and memories were not caused by her nor owned by her nor related to her. These were unrelated mental phenomena which only arbitrarily and artificially were categorized together in "thoughtspace" in a category falsely labeled "hers." When I asked her who was doing the categorization, I got no response.
She also denied the Law of Non-Contradiction, Either-Or, and the Law of Identity.
(Note: I make no claim her conclusions were correct interpretations or deductions from anything taught by internet mountebank Eliezer Yudkowsky; she said so, not I.)
When asked questions or confronted with an error or lapse in her argument, she merely changed the subject and restated her original position, sometimes in different words, sometimes in the same words.
Even those folk foolish enough not to believe in literal demons should admit that possession is real. Otherwise normal and sane folk can be possessed by ideas as unnatural being possessed by unclean spirits, or swept along in the madnesses of crowds.
I saw this happen with a friend. She lives her life on social media. Slowly she went from being a normal housewife to being a transvestite who divorced her husband and changed her name to Constellation to cover all her personalities. She shopped therapists for years until she got one to tell her the diagnosis she wanted. I don't even know her anymore.
For something not existing quite a bit of effort to keep it nonexistent.