What do I know?

How do I know what I know? That is a very good question, I want to think that what I have learned is true, and that things I hear are also true. But do I actually know that everything around me, everything said to me, everything I read is true? No, of course not. And being disappointed by something that I believed to be true but really wasn't is one of the worst feelings you can have. Being sure of something and then it ends up being false and you ideals and hope are crushed. But that situation is only in the most personal sense. If I found out that 1+1=3, to be honest I wouldn't care aside from the fact that all of my math classes since 1st grade have been based of 1+1=2.. So in reality we can only hope that what we know is true. For some things it'll never be clear cut as to right or wrong, truth or lie, black or white.