The Screwfly Solution is a short story by Raccoona Sheldon, in which men all over the world start killing women because they feel a religious voice is telling them it is the right thing to do.
Somewhere in the story, the main character finds a note from a friend reading
Man’s religion and metaphysics are the voices of his glands (Schönweiser, 1878)
This has always intrigued me and I wonder if this is a fictional quote or not. I have never been able to find anything about a scientist named Schönweiser. Has he really existed and is this a true quote from a scientific piece of work?