"When Harry Met Sally" is one of my favorite movies of all time. After recently re-watching that movie, I learned something really important: girls and boys can't be best friends without one of them catching feelings in some way. Now I know that a bunch of you probably just rolled your eyes and thought, "OK this is major BS and so not true, I'm friends with a ton of people of the opposite sex." This theory, however, is not about "friends," it is about best friends.

Best Friends: People who spend the majority of their free time together (one on one in person), talk multiple times a day and discuss personal issues often.

My theory is basically that two people who fall under the title "best friends" can never remain that way without one of them starting to like the other — and here is why.

As human beings, we are first romantically attracted to another person based on their physical attributes, and as time goes on we begin to either hate or love their personality and decide whether or not to continue the relationship. Best friends, on the other hand, go through this process in reverse.

The reason you're best friends with someone is because you like a lot of the same things, you laugh at the same jokes, listen to the same music, and have similar personalities. Physical appearance doesn't really play a role. So when a boy and a girl are spending all this time together, like the same things and pretty much think the same way, one member of the friendship will inevitably fall for the other and a physical attraction will start to grow.

Of course, there are some exceptions to this theory.

1. One half of the boy-girl best friend duo is a homosexual
2. One half of the boy-girl best friend duo is already in a relationship

I know that there are some people reading this that might disagree based on the fact that their best friend is of the opposite sex, however, my theory is that one of you probably likes the other and you just don't know it.

SO! Maybe you should take a look at the guy or girl next to you that you call your best friend and ask yourself whether or not you have feelings for this person or if that person may have feelings for you. After all, there is nothing better than a romantic relationship that starts with friendship!

PS. You're welcome for the advice that you didn't ask for.