I was not screwing around. When I took the first physics class of my life, at age 35, it was at the Massachusetts Institute of Technology, and my professor was Walter Lewin, one of that institution's most respected instructors. Lewin is a man so comfortable with his vectors that he diagrams them in front of a classroom audience while wearing Teva sandals.
OK, I wasn't really "at" MIT. And "took" the class may be a stretch. I was watching the video of one of Lewin's lectures from the comfort of my backyard in Brooklyn, and I too was wearing sandals (but not Tevas; I have standards).