If fiction is defined as what is ‘imaginary’ problems arise because the move renders the phenomenon dependent on authorial intent. Three instances serve to illustrate problems with this approach to defining fictionality. First, suppose Dune, or some other text that describes what is at this point a future time, transpires to be in every detail true. At that later time, it might be remarked that since such a text contains a set of claims concerning events that have come to pass, the text, whatever it’s earlier status, is now non-fiction. If fiction is defined as the imaginary, though, the status of the text cannot be said to have changed: it remains the product of the imagination of the author.
The second case indicative of the limitations of taking fictionality as the imaginary is that in which an author possessed of absurd and erroneous beliefs deploys what he assumes is accurate knowledge of the world in penning a text intended as non-fiction. The world the author believes to be actual appears to me in fact imaginary, a belief world profoundly unlike the world he inhabits. Of course, when this is put to the errant writer, he disagrees, at which point it’s one subjectivity against another with no final arbiter in view.
A third case is the inverse of the second. The author of the previous paragraph decides to have a tilt next at writing fiction, and plumbs the depths of the imaginary in order to produce a rollicking fantasy. The author’s belief system, though, is so at odds with the way things in actuality are that their concept of fantastical worlds includes the actual world at which the text is written. By chance what is written as though fiction proves to be in every detail true.
In this case or the last, the moral of the hypothetical is the same: if we want to say a text is fiction despite the wrong-headed world-view of an author who claims otherwise, it had better be that fictionality is defined in the context of what is externally true or false, actual or possible, and not only in terms of an author’s understanding. Otherwise we leave ourselves unable even to express in an intuitive and unconvoluted way a conviction that the deluded author’s fiction is actually true, and non-fiction in point of fact false.