"There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries."

There are several errors that are not infrequent in the use of metaphor. A metaphor should not be blended with plain language in the same sentence, nor should it be extended too far. The latter fault is called "straining the metaphor." Two incongruous metaphors should not be used in the same sentence. In the following lines from Addison his muse is first conceived of as a steed that needs to be restrained with a bridle, and then as a ship that is eager to be launched:

"I bridle in my struggling Muse with pain,
That longs to launch into a bolder strain."

(3) Personification is the attribution of life to inanimate things. When we speak of "the thirsty ground" or "the angry ocean," we endow these objects with the feelings of living creatures. Personification is a bold species of metaphor; it is the offspring of vivid feeling or conception, and often lifts discourse to a high plane. Thus, in "Romeo and Juliet," we read,—

"Night's candles are burnt out, and jocund day
Stands tiptoe on the misty mountain tops";

and in Shelley's "Queen Mab,"—

"How wonderful is Death,
Death and his brother Sleep!
One, pale as yonder waning moon,
With lips of lurid blue;
The other, rosy as the morn
When, throned on ocean's wave,
It blushes o'er the world:
Yet both so passing wonderful!"

(4) Allegory is the description of one object in terms of another. It is a sort of continued metaphor in which, however, the main subject of discourse is not mentioned. In the following beautiful allegory, the Jewish people are described in the character of a vine: "Thou hast brought a vine out of Egypt; thou hast cast out the heathen, and planted it. Thou preparedst room before it, and didst cause it to take deep root, and it filled the land. The hills were covered with the shadow of it, and the boughs thereof were like the goodly cedars. She sent out her boughs unto the sea, and her branches unto the river. Why hast thou then broken down her hedges, so that all they which pass by the way do pluck her? The boar out of the wood doth waste it, and the wild beast of the field doth devour it. Return, we beseech thee, O God of hosts; look down from heaven, and behold, and visit this vine; and the vineyard which thy right hand hath planted, and the branch that thou madest strong for thyself."[72:1]

The parable and the fable are closely akin to allegory. A parable is a brief narrative of real or imaginary incidents for the purpose of inculcating some moral or religious truth. It has been described as "an earthly story with a heavenly meaning." A considerable part of Christ's teaching was in parables, many of which are as beautiful as they are profound.

A fable is a fictitious story introducing animals or even inanimate things as rational speakers and actors, for the purpose of teaching or enforcing a moral. The fables of Æsop are almost universally known, and the fables of La Fontaine exhibit a high degree of artistic merit.