Working definition
In the narrative sense of the term, a fable is a very brief invented, double-meaning story in which a lesson of every day practical morality is taught. The kind of lesson is one of the points that distinguish fable from parable and allegory. The fable never aims higher than inculcating maxims of prudential conduct—industry, caution, foresight, and the like—and these it will sometimes recommend at the expense of the higher, self-forgetting virtues. A typical fable reaches just the pitch of morality which the world will approve. In spirit the fable is often humorous, often ironical. In diction it is always simple, forceful, and appropriate.
Three classes of fables have been noticed: (1) the rational—in which the actors and speakers are solely human beings or the gods of mythology, (2) the non-rational—in which the heroes are solely animals, trees, vegetables, or inanimate objects, (3) the mixed—in which the rational and non-rational are combined.
Classes of fables
Now what distinguishes all these from myth and legend is the presence of the evident and acknowledged didactic purpose. What distinguishes the first class, the rational fable, from a parable is the low plane of the motive. Above the utilitarian the fable never rises. If the fable teaches honesty, it teaches it merely as the best policy. What distinguishes the non-rational and the mixed fables from allegory is both the limitation of the moral and the kind of hero. The lesson of the fable is always piquant, single, and clear. The actors in a fable are always things concrete in nature as well as in the story.
The most popular, and hence the most typical of the three classes of fables, is the second, often called also the "beast fable." The beast fable departs somewhat from the laws of nature. In the dialogue, animals and inanimate objects act like human beings. A fox and a bear, for instance, will philosophize on politics. A lion and a mouse will exchange courtesies. But it is a remarkable feature of this type of story that we do not resent the incongruity. And that we do not resent it is because there is a truthfulness that is more interesting to us than is the natural order of the universe—namely, the truthfulness of characterization. Here the verisimilitude must be complete. Although acting the part of rational beings, the animals must be true to our accepted notion of their animal nature—a fox must be foxy; a bear, bearish; a lion, haughty; a mouse, timid; a cat, deceptive; a monkey, mischievous; a canary, dependent; an eagle, lofty; and so on, and so on. It is not necessary that they have no other characteristics, but it is necessary that they possess the commonly ascribed ones.
How to write an original fable
To write what is strictly a fable, a person will need to observe the distinctions of the type in general as cut off from parable on the one hand and allegory on the other, and to observe the distinctions of the subdivisions within the type. Then he must decide, of course, which subdivision he is going to follow, must select his moral, pick out his actors, think over their characteristics, and finally narrate a brief occurrence in a vivid, homely style. The dialogue, while correct, should be very colloquial. It is well for one to pay especial attention to author's narrative, likewise, that it may be informing though limited. After all is told, the writer may or may not affix a maxim at the end, definitely and neatly stated. In either case, however, the lesson taught should be unmistakable. Original and spirited fables could be written in the field of civic morals, about which the world has just begun to think seriously. Despite the good work that is being done in the name of charity, there is room surely for pleasant satire when a Happy Childhood Society gives elaborately dressed dolls to naked babies.
If one chooses to write a rational fable, where the actors are human beings, one must be careful not to write a parable. The lesson of a fable is always unsentimentally practical—not spiritual. Where the actors are gods, or gods and men, the student-writer must distinguish fable from myth. He should not aim at explaining a universal phenomenon, but simply at teaching a single, acute, work-a-day lesson.
Armenian proverbs that might be used for fable maxims