Years ago my friend and I took a trip to San Francisco where my friend used to live. One afternoon we decided to stop into this nice little pub for a cocktail. I took the opportunity to snap a picture of my friend. A few days later my friend took me to meet his friend Ed who lived a couple of miles away. I showed Ed the pictures I had taken on the trip. When we came to the picture from the bar, we noticed Ed in the background, through the window, walking by.