Here is what I am thinking...
I can live with stupid people, there are plenty of people who just don't have natural intellectual talent, just like some people are athletic while others aren't. The unfortunate thing here is that these people often times simply don't understand basic educational concepts and begin to fall behind in school. After a while they get sick of it since nobody likes to fail, and most people reach a point where they basically give up, at least somewhat. I've developed this from my sister, who in most definitions of the word would be considered stupid. She is 12 and is unable to spell most basic words, she struggles with multiplication tables, and I question whether or not she has ever actually finished a book in her life. She pays no attention at school and has basically given up on learning, but I think it is actually possible to make my sister an above average student. I decided to try and get my sister to succeed in school a couple months ago, and it is actually having an effect. In about 6 weeks she has gone from failing 3 classes, to having a B/C average and failing none. A stupid person truly can acheive if they are given a structured environment and pushed and willed to do their best. The problem is, that the school system has ignored those of slightly below-average intelligence for so long, that rebuilding that will to succeed intellectually becomes a momentous undertaking.
Rather than having no will, an ignorant person has an overly strong will. The sad thing is that ignorant people are often the most intelligent among us. I would say that Appskier may be one of the most intelligent people on this site, but from what I have seen, especially after the tragedy of sep. 11, he is very ignorant. Unfortunately, ignorant people do not easily change, and a case could certainly be made that it is impossible to change a highly ignorant person. My mom, for example, is very ignorant and has never changed, and will never change. She can make a stereotypical, prejusiced, arrogant, and all over ignorant comment, and you can then provide incredible evidence against what she has said, but it won't change her opinion whatsoever.
I support people who simply lack the intellectual ability to perform well, but I can't stand or tolerate an ignorant person.