The other day I heard someone regarded as a genius say that, in general, they feel like they know almost nothing as they are going about their day to day life.
As in, if you're not doing something on a daily basis, you're not going to be very familiar with it. You may have learned a ton in school, but if you didn't use it this week, you're going to have to recover and dust off that knowledge.
This made me feel better because I feel this way all the time. Up until now I thought that I was just less-than, that my brain didn't work real too good, that I wasn't good at remembering things and applying my knowledge.
Oh, I suspected that life & the brain worked this way, that it wasn't really my fault that I couldn't remember all the things that I have learned—but I'm an insecure little dolt, so I needed a genius to go before me and tell me it was ok.