Suffice it to say that, for some artists, a figure from their past can become so important to them that everything they make, from a certain time onward, is for that figure, or has some trace of that figure in it. While, for other artists, there is no figure, only some feeling or energy, not unlike a spirit, that seems to them to dwell inside them, and to bring about in them, explicably or not, some creative drive that is colored by any number of memories or traits that are particular to them. I suppose, as well, there can occur for an artist a combination of both of these forms of muse.