It didn’t make sense to me – I had attended every single class, I took detailed notes in pretty pens, rewrote my notes on notecards and rewrote them again and again making sure I would remember every key detail and score every point possible.
I learned everything the professor had taught in class and gave it all back to him in great detail, so... maybe he made a mistake in his math? Maybe he skipped grading one of the essays?
After all the other students left, I handed my test to the teacher and said I didn’t understand what I could have missed.
He looked at my exam and handed it back with a short diagnosis. “You didn’t buy the textbook.”
“I *did* buy the textbook!”
“Oh. Then, you clearly didn’t *read* the textbook.”
My 19 year old self crumbled just a little, then asked, “Why do we need textbooks? Your lectures are so good, they cover everything…”
He put his hand up to stop my babble, “No educated person gets all their information from one place. You always need two sources, at least.”
He nodded.
I nodded.
I read the book and earned an A in the class.