No, first of all, you're implying such knowledge must be impossible. I already have an A-level in computing, plus I never said I knew everything, I knew everything save programming. It depends on what you and me classify as everything.
I talk about an IT career because I'm interested in computing and psychology, which is why I took an A-level in both, but branching off to psychology in the end. You may think a phd is a great qualification, that doesn't mean it should stop me trying out other career avenues. 1) everyone is different 2) you should do something you really enjoy and 3) I enjoy both fields and so I want to try out careers in both.
I insult you all because I need to defend myself. You start calling me "dvdbunny" and then laughing that I'm a naive 22 year old...that's classed as an insult too you know?