For what it's worth, I think you gain karma by writing comments that contribute to the discussion. Your comment could have been something informative, perhaps

For what it's worth, I think you gain karma by writing comments that contribute to the discussion. Your comment could have been something informative, perhaps supporting the point of "the guy was a genius", but as written was little more than "nuh uh you're wrong". (I apologize in advance for also not furthering the discussion.)