It is sometimes said that a “good subject” for a short story should always be capable of being expanded into a novel.

The principle may be defendable in special cases; but it is certainly a misleading one on which to build any general theory. Every “subject” (in the novelist’s sense of the term) must necessarily contain within itself its own dimensions; and one of the fiction-writer’s essential gifts is that of discerning whether the subject which presents itself to him, asking for incarnation, is suited to the proportions of a short story or of a novel. If it appears to be adapted to both the chances are that it is inadequate to either.

It would be as great a mistake, however, to try to base a hard-and-fast theory on the denial of the rule as on its assertion. Instances of short stories made out of subjects that could have been expanded into a novel, and that are yet typical short stories and not mere stunted novels, will occur to every one. General rules in art are useful chiefly as a lamp in a mine, or a hand-rail down a black stairway; they are necessary for the sake of the guidance they give, but it is a mistake, once they are formulated, to be too much in awe of them.

There are at least two reasons why a subject should find expression in novel-form rather than as a tale; but neither is based on the number of what may be conveniently called incidents, or external happenings, which the narrative contains. There are novels of action which might be condensed into short stories without the loss of their distinguishing qualities. The marks of the subject requiring a longer development are, first, the gradual unfolding of the inner life of its characters, and secondly the need of pro- during in the reader’s mind the sense of the lapse of time. Outward events of the most varied and exciting nature may without loss of probability be crowded into a few hours, but moral dramas usually have their roots deep in the soul, their rise far back in time; and the suddenest- seeming clash in which they culminate should be led up to step by step if it is to explain and justify itself.

There are cases, indeed, when the short story may make use of the moral drama at its culmination. If the incident dealt with be one which a single retrospective flash sufficiently lights up, it is qualified for use as a short story; but if the subject be so complex, and its successive phases so interesting, as to justify elaboration, the lapse of time must necessarily be suggested, and the novel-form becomes appropriate.

The effect of compactness and instantaneity sought in the short story is attained mainly by the observance of two “unities” — the old traditional one of time, and that other, more modern and complex, which requires that any rapidly enacted episode shall be seen through only one pair of eyes.

It is fairly obvious that nothing is more retarding than the marking of a time-interval long enough to suggest modification in the personages of the tale or in their circumstances. The use of such an interval inevitably turns the short story into a long tale unduly compressed, the bald scenario of a novel. In the third chapter, where an attempt will be made to examine the technique of the novel, it will be needful to explore that central mystery — of which Tolstoy was perhaps the one complete master — the art of creating in the reader’s mind this sense of passing time. Meanwhile, it may be pointed out that a third, and intermediate, form of tale — the long short-story — is available for any subject too spreading for conciseness yet too slight in texture to be stretched into a novel.

The other unity, that of vision, will also be dealt with in considering the novel, in respect of which it becomes a matter much more complicated. Henry James, almost the only novelist who has formulated his ideas about his art, was the first to lay down the principle, though it had long (if intermittently) been observed by the masters of fiction. It may have occurred to other novelists — presumably it has — to ask themselves, as they sat down to write: Who saw this thing I am going to tell about? By whom do I mean that it shall be reported? It seems as though such a question must precede any study of the subject chosen, since the subject is conditioned by the answer; but no critic appears to have propounded it, and it was left to Henry James to do so in one of those entangled prefaces to the Definitive Edition from which the technical axioms ought some day to be piously detached.

It is clear that exactly the same thing never happens to any two people, and that each witness of a given incident will report it differently. Should some celestial taskmaster set the same theme to Jane Austen and George Meredith the bewildered reader would probably have some difficulty in discovering the common denominator. Henry James, in pointing this out, also made the corollary suggestion that the mind chosen by the author to mirror his given case should be so situated, and so constituted, as to take the widest possible view of it.

One thing more is needful for the ultimate effect of probability; and that is, never to let the character who serves as reflector record anything not naturally within his register. It should be the story-teller’s first care to choose this reflecting mind deliberately, as one would choose a building-site, or decide upon the orientation of one’s house, and when this is done, to live inside the mind chosen, trying to feel, see and react exactly as the latter would, no more, no less, and, above all, no otherwise. Only thus can the writer avoid attributing incongruities of thought and metaphor to his chosen interpreter.