I have a low tolerance for stupidity. Let me just say that right now. Stupid people stretch the very fragile boundaries of my patience. If you ever hear a news story about some middle-aged woman on a rampage of punching people in the face, that will be me and my patience finally running out.
Stupidity is not the same thing as ignorance, however. Ignorance means that you don't know better. Ignorance implies a lack of exposure. If you don't know multiplication, for example, that is ignorance. Ignorance can be cured, or at least accommodated; all that is needed is information and a willingness to learn. I have all the time in the world for people who want to learn.
Stupidity is a choice. In the above example, the person doesn't know multiplication, but decides that they don't want to know multiplication. They come up with excuses why multiplication is not worth knowing. Multiplication is the work of the devil. Multiplication kills puppies. Multiplication leads to people having sex(that one might be true; people don't really need a "reason" to have sex). This person chooses to remain ignorant rather than learn something new about the world and the people in it. That is stupidity.
My low tolerance for stupidity extends to myself. If I don't know about something, I make an effort to find out. It especially bothers me when someone tries to tell me what to think; I have to know why they want me to think that. I will not just blindly follow. I have to know where I am going and why. I just don't like the idea of "not knowing", so I choose to remedy that. This is not always fun, and it sometimes makes people angry, but it is necessary.
Knowledge is power. It's the power to decide for myself, to make my up my own mind. I don't always like what I find out; there is some pretty horrific stuff out there, like multiplication. What I learn sometimes completely changes my view of the world. That is okay. I would rather make up my own mind about the world, and my own decisions.