Hyperbole (Greek, excess) is a trope by which more is expressed than is literally true:
I shall strike the stars with my crown.
Hyperbole: More than true
From English Composition and Rhetoric, by Alexander Bain; W. Davidson; Practical Rhetoric, by Albert Raub:
I. In hyperbole, objects and ideas are magnified.
Hyperbole consists in magnifying objects beyond their natural bounds, so as to make them more impressive or intelligible.
swift as the wind
rivers of blood and hills of slain
II. Hyperbole comes naturally.
A. Every strong passion magnifies whatever concerns it.
1. Love, fear, hatred, exaggerate their several objects in proportion to their intensity.
A day in Thy courts is better
than a thousand outside. (intense devotion)
a. Affection has always been permitted to enhance its objects far above their reality.
b. Fear exaggerates danger.
c. Hatred intensifies, and even creates, bad qualities in the person or thing hated.
B. These passions have to be attended to in depicting character.
Anyone under strong passion is represented as magnifying the object of the passion. The terrified scout, in Ossian, is made to describe the enemy thus:
I saw their chief tall as a rock of ice;
his spear the blasted fir;
his shield the rising moon;
he sat on the shore,
like a cloud of mist on the hill.
C. Human desire is limitless.
1. Therefore, whatever pleases us in poetry, or in the fine arts generally, is magnified as far as can be done without offending our sense of reality and truth.
2. It is a function of poetry to please us by presenting pictures of surpassing grandeur or loveliness, taken from nature and from humanity.
a. Accordingly, it raises actual things by the force of elevated description, and by all the arts of admissible exaggeration.
b. On account of this feature of the poetic art, Plato banished poets from his Republic.
c. Bentham styled poetry “misrepresentation in verse.”
D. Exaggeration is often used for comic effect.
As the ludicrous requires that a certain object should be depreciated in some mode or other, this is often done by exaggeration. Voltaire, speaking of England, said “The English gain two hours a day by clipping words.”
III. Hyperbole must be kept within limits.
A. Hyperbole should take into account what the hearer will tolerate in the way of departure from the known reality.
B. It should be used sparingly.
C. It should not be trite.
1. The feelings of those addressed must be sufficiently strong to enable them to appreciate the hyperbolical expression. Few were prepared, in this respect, for Dryden's couplet on Charles II:
The star that at your birth shone out so bright,
It stained the duller sun’s meridian light.
D. Originality is indispensable.
A mere exaggeration is easy; the kind that yields pleasurable surprise must have novelty, grandeur, or point, to recommend it. Plato compared the idea of good to the Sun. Horace speaks of a man “striking the stars with his sublime head.”
The following example is from Shelley:
There was such silence through the host, as when
An earthquake, trampling on some populous town,
Has crushed ten thousand with one tread, and men
Expect the second.
IV. Hyperbole may be used for the purpose of illustrating truth.
We reproach a man for neglecting some common duty by putting it to him what would be the consequences if every one were to be equally remiss.
To show the influence of the mind on the body, it is usual to quote the extreme instances:
dying of a broken heart
killed by grief or joy