Q: Which is correct: “She is smarter than him,” or “She is smarter than he,” or “She is smarter than he is”? The first does sound more idiomatic; the second, snootier; and the third, something in between. I do so rely on your help!
A: If formal perfection is what you’re after, go with “She is smarter than he is” or the admittedly stiff “She is smarter than he.”
Traditionalists still believe that in formal English, “than” is a conjunction and not a preposition, and that the following pronoun should be in the nominative case – “he,” not “him.”
But English is a living language, and the traditional view of “than” has shifted. Usages like “than him” are no longer regarded as incorrect – merely less formal.
This often happens. Over time, a natural usage tends to win out over an unnatural one, and to many people, “than he” is stuffy and unnatural.
As I told a reader once before on the blog: “Some usage gurus, including William Safire, accept ‘than’ as a preposition, and claim the object pronoun (‘me,’ ‘him,’ ‘us,’ and so on) afterward is just fine. Certainly common usage is on their side.”
So my advice is to use the natural-sounding “than he is” or “than him,” and save “than he” for the most formal occasions. “Than him” is certainly more usual in conversation and is considered standard by many respected authorities.
Lexicographers are already arriving at this conclusion, though usage experts may disagree.
Bryan A. Garner, in Garner’s Modern American Usage, makes the usage expert’s case: “For formal contexts, the traditional usage is generally best; only in the most relaxed, colloquial contexts is the prepositional than acceptable. Often it seems ill-advised.”
Now for the lexicographers.
The American Heritage Dictionary of the English Language (4th ed.) says “than is quite commonly treated as a preposition when followed by an isolated noun phrase, and as such occurs with a pronoun in the objective case: John is taller than me.”
“Though this usage is still widely regarded as incorrect,” the dictionary continues, “it is predominant in speech and has reputable literary precedent, appearing in the writing of such respected authors as Shakespeare, Johnson, Swift, Scott, and Faulkner.”
But American Heritage warns that “the writer who risks a sentence like Mary is taller than him in formal writing must be prepared to defend the usage against objections of critics who are unlikely to be dissuaded from the conviction that the usage is incorrect.”
However, Merriam-Webster’s Collegiate Dictionary (11th ed.) accepts the prepositional use of “than” without reservation. It defines “than” in this case as meaning “in comparison with” and gives the example “you are older than me.”
A usage note in M-W concludes: “In short, you can use than either as a conjunction or as a preposition.”