Anyway, it seems to me that librarians must deal with
this sort of thing all
the time. And the many public libraries that use the Dewey Decimal system
can't just fall back on the Library of Congress. Although perhaps there's
some central authority that recommends Dewey classifications. But in any
case, someone has to decide whether Velikovsky is science or science fiction.
Who does? and how?
Quite often, this will be done by the publisher (certainly in my
experience with school libraries), who will put a Dewey number on the
copyrights page. Not exactly neutral, but that's the way it seems to
be done as far as I can tell.
Sam