prosfilaes
Adventurer
Not so! Adventurers are not made of finer clay than other mortal men. What one man can do another may emulate equally well.
In the real world, it's not that simple. There's many people who try to be the next Usain Bolt, Tiger Woods, Albert Einstein or Kurt Gödel, but not many people who even come close. In a lot of fantasy worlds, you either have the magical spark or you don't; Dudley could never have made it at Hogwarts. In a D&D setting, I wouldn't find it at all unreasonable to think that you have to be born with a certain something to take a level in a PC class.