There are several ways of misquoting Shakespeare.
One is to misquote Shakespeare without knowing it’s Shakespeare at all. Most people who use the phrase “to gild the lily” probably fall into that category, unaware of the original version.
King John Act 4, Scene 2:
SALISBURY: […] To gild refinèd gold, to paint the lily, to throw a perfume on the violet, to smooth the ice, or add another hue unto the rainbow, or with taper-light to seek the beauteous eye of heaven to garnish, is wasteful and ridiculous excess.
Another is to know the quote is from Shakespeare, but to mangle it in some standard way. As in, “Alas, poor Yorick, I knew him well.”
Hamlet Act 5, Scene 1:
HAMLET: […] Alas, poor Yorick. I knew him, Horatio—a fellow of infinite jest, of most excellent fancy.
A third is to get the words exactly right, but to misunderstand the meaning. Which is where wherefore comes in.
Romeo And Juliet Act 2, Scene 1:
JULIET: O Romeo, Romeo, wherefore art thou Romeo?
Generations of amateur actors and parodists have uttered this line as if wherefore were a synonym for “where”, leaning emphatically on the third-last word and adding a comma before the last: “… wherefore art thou, Romeo?” Sometimes they scan an imaginary horizon anxiously. Occasionally they shade their eyes from the sun with one hand, apparently forgetting that the balcony scene takes place at night.
But Juliet is asking why Romeo is Romeo. Specifically, she wants to know why Fate has seen fit to make the man she loves Romeo of the House of Montague, a family with which her own family, Capulet, has a feud. So the emphasis is on the last word, and no comma: “… wherefore art thou Romeo?” Because life would be so much simpler if he were some other (non-Montague) guy. As she says, using another phrase that falls under Misquotes We Don’t Know Are Shakespeare: “That which we call a rose by any other word would smell as sweet.” *
The erroneous version ofJuliet’s wherefore has become a snowclone, spawning thousands of copy-cat phrases of the same form. A quick on-line search turns up examples like, “Wherefore art thou, telecollaboration?” “Wherefore art thou, Colin Powell?” and, inevitably, “Wherefore art thou, Shakespeare?” all with that tell-tale extra comma.
Why does wherefore mean “why”? Because it’s a cousin to therefore. The trio there/where/here have spawned all sorts of families of words, all operating from similar templates. In this case we have:
therefore: for that reason, there
wherefore: for which reason, where?
And yes, since you ask, there once also was:
herefore: for this reason, here
There are also thereabouts/whereabouts/hereabouts, thereto/ whereto/hereto, thereat/whereat/hereat, thereby/whereby/hereby, theretofore/wheretofore/heretofore and a host of other triads, all operating in the sense of “that, there” / “which, where?” / “this, here” added to some preposition or adverb to come up with a new word. Shakespeare used a lot of them; in Modern English we’ve lost a large proportion, except in hold-out areas like legal language.
Wherefore is one that doesn’t see much use any more. And the only use it does get is as a noun, which just adds to the confusion. A wherefore is a reason—in effect, an answer to the question “Wherefore?”
If you feel that you’ve never seen that usage before, it’s probably because it persists only in the plural, and in the stock phrase “the whys and wherefores” meaning “all the reasons”.
The expression used to be singular (“why and wherefore”) but the plural certainly emphasizes a sense of exhaustiveness: “We need to know ever one of the reasons, all the whys and wherefores.” So this time I’m not going to claim the phrase as another Shakespearian misquotation.
A Comedy of Errors Act 2, Scene 2:
DROMIO OF SYRACUSE: Was there ever any man thus beaten out of season, when in the why and the wherefore is neither rhyme nor reason?
* Actually, there’s some doubt about whether Shakespeare wrote “word” or “name”.