So back when I was just a young adult (early 80s) I got my first job as a pizza delivery man. I get an order for a large pizza and a few bottles of coke. The drive seemed like forever since it was in upstate and my heat didn't work in that winter night. I finally make it and hope the pizza isn't cold by then since I really needed the tip money. I knocked on the door. No answer. I was freezing, yet determined to deliver the pizza. I knock again and finally an answer. It was an older guy and I could tell that he probably just got done with a doobie. The smell was obvious, but I smoked at the time too so I didn't think too much of it.
The man had forgotten his cash and told me to come in and warm up while he found his check book. He left away to another room while I warmed in the front hallway. That's when it hit me. I knew this guy. He was famous for something and I saw him on TV all of the time. I'm trying to remember what show I've seen him from and can't even think of it by the time he gets back. His face looked less happy than when I first came and he said, "I'm so sorry that I cannot find my checkbook at the moment. I know you've driven a long way and I want to pay you. How about you sit down for a bit, have some pizza and I can pay you with something more valuable than any amount of money. I can give you knowledge."
That's when I figured it out. That man was Carl Sagan.