To whit or to wit?

Which is correct?
According to Peter Cohan, there are six reasons Facebook stock is only worth $7, _____: competing objectives, slowing growth, conflicted ownership structure, weak monetization, lack of user privacy and overvalued shares.
a. to wit
b. to whit

Answer: a.

Explanation:
To wit means namely. To whit doesn’t mean anything. A whit is a teeny, tiny amount. You might say, for example, that you care not a whit that Mark Zuckerberg lost $8 billion in that IPO — especially since he’s still got several more billions (reportedly 9.4 of them) to tide him over. That should keep him in hoodies and running shoes for a while.

That example is how the phrase is generally used, too: I care not a whit, rather than I don’t care a whit. If I care not a whit seems a little starchy to you, there’s a rhyming expression that’s more in the common vernacular: I don’t give a ____. Essentially means the same thing but won’t have your friends making fun of you.

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The Grammarphobia blog explains more about to wit:

In Anglo-Saxon days, a now-archaic verb “wit” meant something like to know, according to the Oxford English Dictionary. The OED’s earliest example of this usage is in King Alfred’s translation of Boethius from around the year 888.

The expression “to wit,” first recorded in 1320, originally meant “it is to be observed, noted, or ascertained.” Later (around 1400), it came to mean “to be sure” or “indeed” or “namely.”

The “wit” part of the phrase was written all sorts of ways for the first few hundred years: “wite,” “witen,” “wetynge,” and so on.

It wasn’t until the late 16th century that the expression “to wit” took on its modern meaning: namely or that is to say. The earliest citation in the OED (from 1577) says “the beginning of vertue is of Nature, to wyt of Perfect Nature.”

As a nature junkie, I especially like this citation from an 1875 book about the history of Maine: “Thrice nine ridges … to wit, nine of bog, nine of smooth and nine of wood.”

If you’d like to read more about Peter Cohan’s valuation of Facebook, his Forbes post is here.

Follow me on Twitter @tao_of_grammar