Given my present understanding of my ubiquitous lack of understanding of the world in general, I can't help but smile just a bit when I think about my beliefs when I was around 15 years old.
I was in 10th grade at the time and good god did I ever have it all figured out. On a pretty consistent basis I would use words like "ignorance, short sighted and unaware" when talking to my mother; and I guess probably most other people that had the misfortune of chatting with me....