Deja vu

Date: 9/6/2017

In class today explaining to the students how to prepare for the test when I feel deja vu. I remember the original time, a dream, and I didn't remember the faces, but I realize the faces in front of me are the ones I had dreamt of before. It felt so surreal. That wasn't the first time I've felt it teaching. But why do I feel it so often when I teach?