That there be always an apparent Chain or Connexion, or else an obvious Agreement or Contrast, between the two Subjects, is absolutely requir'd, in order that the Auxiliary one may be justly introduced; otherwise, instead of Wit, there will only appear a rambling Vivacity, in wild, unprovoked Sallies.
And yet every just or natural Introduction of an auxiliary Subject will not produce Wit, unless a new Lustre is reflected from thence upon the original Subject.
It is further to be observed, that the Introduction of the auxiliary Subject ought not only to be just, but also unexpected, which are entirely consistent together; For as every Subject bears various Relations and Oppositions to other Subjects, it is evident that each of these Relations and Oppositions upon being exhibited, will be unexpected to the Persons, who did not perceive them before; and yet they are just by Supposition.
It is upon such unexpected Introductions of auxiliary Subjects, that we are struck with a Surprize; from whence the high Brilliancy and Sparkling of Wit, result.
Whereas Auxiliary Subjects, introduced upon such Occasions, as they have been frequently exhibited before, are apt to fall dull, and heavy upon the Fancy; and unless they possess great natural Spirit, will excite no sprightly Sensation.
It is also necessary to observe, that, in Wit, the Subjects concern'd must be ordinary and level; By which are intended, not such as are common, but such as have no extraordinarily exalted, or enlarged, Qualities; and are not unsizeable in the particular Circumstances in which they are compared to each other;--otherwise it is easy to perceive, that the Result of their Arrangement will not be so properly Wit, as either the Sublime, or Burlesque.
To all this is to be added, that either Gallantry, Raillery, Humour, Satire, Ridicule, Sarcasms, or other Subjects, are generally blended with Wit; It has been for want of this Discovery, and of a proper Separation of these Subjects, that the Attempts which have hitherto been made to define Wit, have been all involv'd and overwhelm'd in Perplexity; For the different Mixtures of these foreign Ingredients with Wit, have discover'd such various and opposite Colours and Substances, as were impossible to be comprehended in one certain steady Definition;-- Whereas pure Wit alone, constantly appears in one uniform Manner; which is, In the quick Elucidation of one Subject, by unexpectedly exhibiting its Agreement or Contrast with another Subject.
It is proper in this Place, to distinguish between Wit, Similes, and Metaphors. Similes, though they illustrate one Subject, by arranging it with another Subject, are yet different from Wit, as they want its sudden and quick Elucidation.
Again; In Wit, the Elucidation is thrown only upon one Point of a Subject; or if more Points be elucidated, they are so many different Strokes of Wit;-- Whereas every Simile touches the Subject it illustrates in several Points.
It is from hence, that the Elucidation, as before mention'd, arising from a Simile, is slower than from Wit; But then is is generally more accurate and compleat;--In short, Wit, from its Quickness, exhibits more Brilliancy, But Similes possess greater Perfection.