Is there a link between mental illness and genius?

There's a saying that there's only a thin line between being crazy and being a genius. I dont really know about that. My take would be genius people have a lot of things to think about, they want to do something very revolutionary or feel like they dont belong somewhere so they tend to spend time alone doing their stuff. Maybe they also think that other people are just doing normal stuff and they dont want to mingle with them. Sometimes they also get bored at school or with other people their age that dont have the same level of thinking as them so they tend to just be alone or look for other people or things to spend their time with. I dont really think that's being crazy but it's just that they have other priorities or have interests different from those people they are expected to mingle with.

Real smart and intelligent people know how to adjust their thinking to other people's level. They may have difficulties fitting in but they know that this is such the case and can adapt accordingly. What you say is true too that because of their level of intelligence, people around may find it difficult to get along with them.

i saw the the film "a beatiful mind",it's a very sad story about a genius of economics and math.many genious are not ordinary person,they feel alone because their ideas could n't be exchanged to ordinary people.

Booker T. Washington once said something like Genius is doing a common thing in an uncommon way. What makes you a genius or a very smart person is probably that you think outside the box and you think outside the system we are all sucked into from birth. I bet that if a very smart person is around average people they can't truly speak their minds because the majority may not except their thoughts. This happens through out history with the most esteemed intellectuals, infact Einstein said that, "Great spirits have always encountered violent opposition from mediocre minds". Basically, the majority doesn't usually adapt easily to change and thats what genius' bring about since their ideas and thoughts are outside the box. So maybe the smart persons just try not to talk too much in order to somewhat agree to disagree.

I think it's possible that there is a link between the two. More extensive research needs to be done on this topic. Stephen Hawkin, one of the great minds of the 20th century is in someway mentally hanicapped but writes books on astrophysics and deep matters of space. But it wouldnt surprise me if there is a interconnection of the two mind conditions.