Sometimes the I's don't have it

You may not have written more columns than I. You may not be any better educated than I. But if you approve of my grammar in this paragraph, you certainly have a stronger stomach than I.

A lot of people know and even more suspect that "I" is usually the right choice to go after "than" in cases such as the ones above. But no way are they going to talk this way. And, if you're one of them, then you're just like me.

Getting the jargon out of the way, the rule we're dealing with here has to do with using the nominative case (subject pronouns such as he, she, we and they) and not the objective case (object pronouns such as him, her, us and them) in these types of constructions.

I break a lot of grammar rules in my day-to-day life, and even in this grammar column. And for me, there are rules for knowing when to break the rules.

Rule-breaking rule No. 1: The grammar rule in question is so stuffy and old-fashioned that observing it would make me sound snooty.

Rule-breaking rule No. 2: Someone better-qualified than me must also advocate breaking the rule. I simply don't have the clout to go blazing new grammar trails. Someone like William Safire, however, is another story.

Rule-breaking rule No. 3: When most of the people who advocate a rule can't fully explain it, then, in my book, it's fair game.

Rule-breaking rule No. 4: I must fully learn a rule before I can, in good conscience, stick it where the sun don't shine.

So whether you love this "than" rule or hate it, here's your ammo.

"Than" is primarily a conjunction. Conjunctions introduce whole clauses. A conjunction does not take an object the way a preposition does. In the sentence, "Strict constructionists would like to throw darts at me," the word "me" the object of the preposition "at." But, "Strict constructionists have more credibility than I" technically requires "I" instead of "me" because "than" can only set up a clause. And -- here's the clincher you've suspected all along -- clauses have verbs, even when they're only implied. Therefore you need a subject to perform the action in the verb. The "than I" in this case is shorthand for "than I do." "She is taller than I" is really just an abbreviated "She is taller than I am."

But that does not mean that "I" is always the right choice. In, "Mom loves you more than me," the clause introduced by "than" has omitted not just its verb but also its subject. This sentence really means, "Mom loves you more than she loves me." Which is why it's shortened to, "... than me."