[psygnisfive]

Pay no mind to the people who commented before me.

The phrase that follows the comparative preposition "than" is not necessarily a reduced clause. It's actually almost always a simple noun phrase, taking the default accusative case.

"I am taller than him" is Standard American. If you were to say "I am taller than he" you'll sound like a twat.

Doesn't make sense? So what. Language isn't about making sense, it's about getting points across. There's plenty more in English that's even more confusing (exceptional case marking? oh yeah, baby, figure that one out).

Hell, even if it WERE a reduced relative clause there are plausible reasons why it could still be "him", namely, "nominative" and "accusative" are structural case, not semantic case, so they get assigned depending on the assignee's position in the sentence structure, and you could easily reduce a clause and, in doing so, put its subject into precisely the structure necessary for accusative case.

[kelnos]

As an alternative to poor grammar and sounding like a twat, one might simply say, "I am taller than he is." Sure, it's an extra word, but it's both correct and sounds natural.

I struggle with that occasionally. Using "him" in that sentence would make me die a little inside, but I also don't want to sound like a prick.

[psygnisfive]

Speaking of comparatives, a fellow grad student here at the University of Maryland is working on a phenomena called the comparative illusion, which involve sentences like the following:

More people have been to Russia than I have.

Think about that one for a bit. LL did a post on it, btw: http://itre.cis.upenn.edu/~myl/languagelog/archives/000860.h...