You are walking through a park on a pleasant autumn day. There are leaves falling gently from the trees and people enjoying the cool weather. As you walk along the paved path, you notice someone sitting on a nearby bench. As you pass by, your eyes briefly meet. You continue on for a few steps but then something makes you turn around. You walk back over to the bench and smile. "Beautiful day, isn't it?" you say. The person on the bench, smiles back and replies "Yes it is"