Only factor that Pedro is not weighting is that you have no freakin idea of what you like or what is best for you at 18
Really, mostly it's just a lottery. But most of the times you learn to embrace the choice you have made.
Also, it's never too late to change. You can do anything you want. You just have to want it bad enough. If you, you will get there whether it is at 18, 20, 28 or 40 years old.
Med School is the same. I love this semester and the subjects I am having. Still, I have no idea what I want to do with my life.
Some people already know what they wanna do
Since I don't know George? I have no idea, but he seems to like math so he can try do smth related to that.
He can try for a year, if he don't like he can change ( yes that was what you said
), I know lots of people that went to law school, did the first year of the course and then got bored and changed for History, psychology etc.
Others did the full 4 years and then did another course because they realised that it was not what they wanted. It happens a lot.
Btw, I have lots of colleagues with more than 60 years, some of them allways wanted to do law school but never had the opportunity so they're doing it now and having really good grades, they rock
So George? take your time, it is an important decision but it's not like you're choosing your wife, well you can allways exchange that latter too but that's not very cool