There is a scale for belief, from -10 to 10, from impossible to certain. People believed that after they die, they will go to hell, but there is no proof saying that hell exists, so why people still think they would go to hell after they die? People believe in things for their own benefits, for instance, back into medieval period, people would believe in church because if they don’t they will get in trouble, although church might be wrong.
There are three kinds of belief, a vague belief, a well-supported belief, a belief that is beyond reasonable doubt. A vague belief could be explained as eating fish helps you concentrate; a well-supported belief could be understood as I believe that my teacher gave me too much homework because it took me five hours to finish it all, but other students only took one hour, so is it because I am too slow or the teacher gave us too much. A belief that is beyond reasonable doubt, for example, on sept.11, 2001, the World Trade Centre collapsed.
Belief has limitations, in the role of judgment, the danger of gullibility, and the danger of skepticism. When people ask you what is the real world, and do you believe in this world, what would your answer be? Gullibility can be dangerous, people believe in Yahoo! Answers, Wikipedia, and we use them for our homework, but are they reliable? And for what reason we believe in them? There are many people believe in science and/or theories (I will include mathematics within this), but science can mislead us into believe in it, here is a math equation proofing that 1+1 actually equals to 0 or 1:
a=1, b=1