When you look at what many great accomplishments, you often find a person that had a drive to succeed in his field that bordered on an obsession. When you are truly so passionate about something that it becomes your entire life, I believe it is possible to appear as if you are a genius, or maybe to even become one. In fact, I think that true genius can be attributed more to hard work than anything else.

Look at people like Bobby Fischer, he spent an unhealthy amount of time playing / studying chess (supposedly like 18 hours a day), and it destroyed every other relationship in his life. I'm sure he was intelligent, but without developing an obsession with chess, he probably wouldn't have been much of a player.

There was also a kid whose father forced him to study every waking moment, according to an IQ test, he was a super-genius (I think it was over 200), but in reality he was just a poor kid with a fucked-up, abusive father. I remember reading about it in the news, but I can't seem to find the article.