When it comes to geniuses, a few archetypes generally come to mind. They're often characterized as under appreciated geeks with hearts of gold (think the entire cast of Revenge of the Nerds) or as slightly spaced out but cuddly old men (think Einstein). Or they're quixotic coyotes forever trying to nab that pesky road runner. In any case, the word "noble" probably applies, at some level, to most conceptions of the intellectually gifted.
This is not true of John Nash, the subject of the biography A Beautiful Mind. He's a total a-hole.
In fact, judged by the contents of the quite detailed book, Nash is a grade A jerk, the kind of guy you'd rather punch in the teeth than appreciate or get to know. Here's a guy who constantly belittled those around him, refused to support his illegitimate son in any way, demeaned his wife, harbored jealous grudges against those few who bettered him, periodically erupted in violence when thwarted, and was generally contemptuous of you or anyone like you. Really, his ego, misogyny, racism, arrogance and general prickishness knew no bounds.
Thing is, the same could be said for his intellect and his ambition. He was apparently one of the most brilliant mathematicians of the last century, and his character is made more interesting by the fact that he often went about solving mathematical problems in unique and revolutionary ways that broke new grounds in various fields. I can't imagine what it would be like to be that smart, but it's fun to try. The author of his biography, Sylvia Nasar, does a great job of making his life's story interesting, even before we get to the part where the brilliant mathematician tragically plunges into the dim depths of schizophrenia, only to slowly awaken years later just in time to receive a long-overdue Nobel prize. Though age and mental illness have mellowed him greatly, Nash was an interesting character all through his life (and he is, in fact, still alive). Nasar makes this all accessible by stitching together many fascinating episodes into one whole narrative, repeatedly using themes of "genius, madness, and awakening."
Parenthetically, this book is much more complete than the 2001 movie of the same name. In fact, there's really very little overlap between the two. The movie contrives scenes for the sake of drama and totally glosses over critical aspects of Nash's life, such as his bisexuality, the ignoble way he treated his first family (including an illegitmate son) in Boston, or even that whole "math" thing he was so good at. Also, Nash's general "jerk-ishness" is really toned down in the movie, despite being on center stage in the book. And that whole "imaginary best friend/roomate" thing from the book? Apparently never really happened in the book or real life, dramatic as the reveal was in the movie. So even if you've seen the movie, I recommend the book; there's lots more to learn. The only downside of the book relative to the movie is the conspicuous absence of Jennifer Connelly.