Writers are often asked where they get their ideas, and I've heard that question labelled 'silly'. I think the criticism is unwarranted, as what is being asked for, in effect, is an explanation of the creative process. While that may be impossible to do fully and satisfactorily, there are surely sufficient identifiable 'germs' of an idea (in whatever medium it might be) for an artist of any kind to outline a work's genesis.
Neil Gaiman sums it all up nicely here, while Diana Wynne-Jones, in the piece 'Answers to Some Questions' in Reflections on the Magic of Writing says, "My very favourite form of [the question] was asked by a twelve-year-old: 'Where do you get your ideas, or do you think of them for yourself?' Very shrewdly put, because some part of an idea, if it is going to start a book developing, has to relate to something outside me, even if I don't exactly get it from this outside thing. It has to be a creative mix of interior and exterior notions ..."