[gdsimoes]

I had a teacher in the University who took some courses taught by Feynman and had the same experience. He even tried to record some of the lectures, but the result was similar. While he was listening, he felt like everything was very clear. But as soon as he stopped the tape, nothing made sense anymore.

[AlexCoventry]

The funny thing is, if I remember his autobiographies correctly, he wouldn't let anyone else get away with that. I think he said that if he didn't understand something, he would always ask about it.

[cellularmitosis]

“That which I do not understand, I cannot create”

[p1esk]

I also had a prof who took Feynman’s classes. He told us Feynman was a tough grader - he didn’t give partial credits, you either solved a problem or you didn’t.