From The Art and Popular Culture Encyclopedia
A moral lesson is a term in narratology used to denote the educational value of a work. Moral lessons can be found in fables, emblemata, wisdom poetry, exempla, bestiaries and traditional stories. The moral lesson (the "moral") is usually found at the end and may be expressed explicitly in a pithy maxim.
As an example of the latter, at the end of Aesop's fable of the Tortoise and the Hare, in which the plodding and determined tortoise wins a race against the much-faster yet extremely arrogant hare, the moral is "slow and steady wins the race". However, it can also be interpreted that arrogance or overconfidence in one's abilities may lead to failure or the loss of an event, race, or contest. Undermining another persons ability based on image is another message or moral trying to be conveyed. The use of stock characters is a means of conveying the moral of the story by eliminating complexity of personality and so spelling out the issues arising in the interplay between the characters, enables the writer to generate a clear message. With more rounded characters, such as those typically found in Shakespeare's plays, the moral may be more nuanced but no less present, and the writer may point it up in other ways (see, for example, the Prologue to Romeo and Juliet).
Throughout the history of recorded literature, the majority of fictional writing has served not only to entertain but also to instruct, inform or improve their audiences or readership. In classical drama, for example, the role of the chorus was to comment on the proceedings and draw out a message for the audience to take away with them; while the novels of Charles Dickens are a vehicle for morals regarding the social and economic system of Victorian Britain.
Morals have typically been more obvious in children's literature, sometimes even being introduced with the phrase, "The moral of the story is …". Such explicit techniques have grown increasingly out of fashion in modern storytelling, and are now usually only included for ironic purposes.
Some examples are: "Better to be safe than sorry", "The evil deserves no aid", "Be friends with whom you don't like", "Don't judge people by the way they look", "Sticks and stones will break my bones, but words will never hurt me" and "Slow and steady wins the race". Or, "your overconfidence is your weakness."