did he ever meet robert louis stevenson? yes, indeed. very fond of stevenson. did not know him for long. basically it is he and mark twain you come up with this idea of the submerged audience. he talks about they're discussing this in washington square in new york. stevenson is out there. he has to stay warm. he liked him, did not have of long correspondence with him, unfortunately. >> can you talk of a bit more about submerged audience? it is an interesting concept. >> you can read it for yourself. don't rely on my summary. the section, the very beginning of the final form. basically he proposes, he talks about this person who has published all kinds of practical books, how they do this, piano playing, very practical books which he discovered that sell in enormous quantities. he discovered this from a book seller. he had never heard of this kind. the editors figured out this is not davis, but a guy named dick. all kinds of practical books that sold in the millions. the idea is that this is someone who was unknown to the normal world, if you will, the popular w