Howard, I think it depends on what you mean when you say "own". I think we agree that Gauguin still "owns" his work, as Van Gogh does, in that we remember that there is a connection to the artist and usually we don't care who paid for it last.
There is a difference in a piece of work being put up in the context of this forum, perhaps for discussion, and a piece of work hanging in a gallery or in a museum. The public will evaluate and critique the work, quite naturally, without the participation of the author.
The first evaluation is whether a person will actually purchase the art. This is not the only criteria that can be used to value a work as there are clearly those who, however they might esteem the work, will not be in a position to purchase it.
The final evalution is whether the work remains in view or is stored away.