Jokes and shtuff

Here's a quick semi-joke I thought of this morning while listening to one of the wonderful Shluchim give an even more wonderful Shiur on the day's Chumash. Basically, Jacob fights this angel guy and gets a name change. Wouldn't it be sick if he had just gotten like four thousand personal address labels and now had to change them?
Enjoyed my little semi-joke? It was funnier at the time. Anyway, during Mincha I remembered a beautiful Vort from the Rosh (same as last time, Mr. Editor). It doesn't make sense that a person only gets their Yetzer Tov (good inclination) from 13 while they're born with a Yetzer Hora (evil inclination). After all, babies are really cute, and even kids are relatively innocent. When they reach 13 is specifically the time when the evil urge takes over! So what's the story?
What is the YH exactly? He's not necessarily an evil monster. His whole point is himself. The YH makes a person focus only on themselves. A baby's whole existence is himself. Sure it's cute and all, but it's the work of evil. When a kid turns Bar Mitzvah he finally realizes (hopefully) that he's not the only person in the world. This is what it means when a person gets a YT, that he understands that he is not the only existence in the world. Some people, unfortunately, never get this fact. They can be nice people, generous people, but it's all because of them.
Right? Good.