Lucas Humboldt of Richmond, Virginia, writes, "Dear Mr. Wm.™ Steven Humphrey: I am nine years old. I like the Olsen twins. They are nice. I like them. But they are twins, and I can't tell the difference. What is the difference? Thank you, Mr. Humphrey. You are nice, too."

Lucas, you perverted sack of crap. I think it's pretty apparent what this so-called "innocent request" is all about. Just like every other guy in the world, you've got your pee-pee bloated with blood over the fact that Mary-Kate and Ashley Olsen just turned 18 years old! You want to have SEX with them, and I bet you even have one of those weird counters on your computer that was ticking down the minutes until the Olsen twins came of legal, and thereby porkable, age. You, sir, are a sicko FAWK.

Well, I for one am not going to play to your disgusting, pedophilic urgings. Instead, I choose the moral path, strongly encouraging you to seek out psychological counseling. Then I'll turn your name over to the FBI. Screw the Olsen twins? It would seem YOU are the one who is SCREWED. Ha-HA!

However, while Lucas is undoubtedly an obscene syphilitic deviant whose filthy fingers are coated with the stench of three-day-old DNA... he kind of has a point. How do you tell the difference between Mary-Kate and Ashley Olsen? Well that's for me to know, and for lucky YOU to finally find out! But first, some fun and fancy-free facts about the Olsen twins...

FACT! Mary-Kate and Ashley are not identical twins... they're fraternal. Which, apparently, is something different.

FACT! Mary-Kate and Ashley were only one year old when cast on the hit TV show Full House, and four years old when they became demanding bitches.

FACT! Mary-Kate and Ashley's biggest success has been in straight-to-video films, such as To Grandmother's House We Go, and Double, Double, Toil and Trouble. (Both of which were far superior to later offerings such as You're Invited to Mary-Kate & Ashley's Mall of America Party. While certainly whimsical, it lacked the philosophical underpinnings and depth of earlier work, such as How the West Was Fun.) They are now ba-zillionaires.

But the question remains: How are the Olsen twins different? Though each is a multifaceted individual, here's a quick primer on how to tell the difference if you happen to wind up in the same hot tub.

Mary-Kate: Younger by two minutes. Dyes hair brown. Fave items: Cashmere blanket, cell phone, iPod. Fave movie: Labyrinth. Fave school subject: English. Wears a size 5.5 shoe. Played "the wild one" in New York Minute. Conceived thanks to an injection of monkey DNA. Ranked #61 in FHM's "100 Sexiest Women" poll. Will never sleep with you in a billion years.

Ashley: Older by two minutes. Dyes hair blond. Fave items: Cashmere blanket, cell phone, credit card. Fave movie: Pretty in Pink. Fave school subject: Math. Wears a size 5.5 shoe. Played "the other one" in New York Minute. Conceived thanks to an injection of troll DNA. Ranked #61.5 in FHM's "100 Sexiest Women" poll. Will consider sleeping with you in a billion years, if it will raise her ranking from #61.5 to #59.7.

There. Now will you please get some counseling?