Nature and Nature's laws lay hid in night;
God said, "Let Newton be," and all was light.
The first line of the couplet is also usually a self-contained phrase, though more lightly end-stopped than the second; seldom is there much enjambment within the closed heroic couplet.
When skillfully executed, the closed heroic couplet compresses so much meaning into so few words that the effect can be either incisively intelligent, explosively witty, or both. Sometimes the structure of the couplet may seem more rhetorical than poetic, but for those whose ears are attuned to delicate reversals and counterpointing, the poetic "music" of this kind of poetry can be satisfying--even exciting. Here the placement of the caesura becomes important as a means of varying the rhythm.
Although earlier examples of closed heroic couplets can easily be found, John Dryden perfected many of its possibilities for satiric purposes, as we see in his description of Thomas Shadwell in Mac Flecknoe:
And pond'ring which of all his sons was fit
To reign, and wage immortal war with wit;
Cry'd, 'tis resolv'd; for nature pleads that he
Should only rule, who most resembles me:
Shadwell alone my perfect image bears,
Mature in dullness from his tender years.
Shadwell alone, of all my sons, is he
Who stands confirm'd in full stupidity.
The rest to some faint meaning make pretence,
But Shadwell never deviates into sense.
Some beams of wit on other souls may fall,
Strike through and make a lucid interval;
But Shadwell's genuine night admits no ray,
His rising fogs prevail upon the day:
Besides his goodly fabric fills the eye,
And seems design'd for thoughtless majesty:
Thoughtless as monarch oaks, that shade the plain,
And, spread in solemn state, supinely reign.
For Pope, in his Essay on Man, the closed heroic couplet became a vehicle that conveyed a sense of calm and optimistic rationality:
Then say not Man's imperfect, Heav'n in fault;
Say rather, Man's as perfect as he ought;
His knowledge measur'd to his state and place,
His time a moment, and a point his space.
If to be perfect in a certain sphere,
What matter, soon or late, or here or there?
The blest today is as completely so,
As who began a thousand years ago.
Here is an earlier (mid-seventeenth-century) example:
TO RUFUS.
That no fair woman will, wonder not why,
Clap (Rufus) under thine her tender thigh;
Not a silk gown shall once melt one of them,
Nor the delights of a transparent gemme.
A scurvy story kills thee, which doth tell,
That in thine armpits a fierce goat doth dwell.
Him they all fear full of an ugly stench:
Nor 's 't fit he should lye with a handsome wench;
Wherefore this noses cursed plague first crush,
Or cease to wonder, why they fly you thus.
--Catullus, trans. by Richard Lovelace