Open Door Obligation

The basis for this theory is a story.

Background: Going into the back of the med school there are two doors that are always closed but never locked. They are the doors between the med school and the dental school. I park my bike near there.

One day when walking into the school I was clipping my bike helmet onto my back pack and noticed someone walking close behind me. When I reached the first door I pulled the door open I stepped to the side, held the door, and allowed the person to walk through. 7 feet ahead he did the same thing for me.

Throughout the next few weeks I noticed this happening many times. Most buildings around the med school have a foyer where you open one door only to be in a small room in front of another door. This room is to control the temperature in the main building but it creates this amazing social situation.

When one person opens a door for you, most people feel the obligation to open the next door.

Negative Spin: People don't like the feeling of owing something to you for your gesture. Because of their sense of debt they use the opportunity to repay you immediately and level the playing field. Why don't people just accept the free gift of uninterrupted walking.

Positive Spin: Your gracious gift encourages their selfless act as well.

Disclaimer: This all changes if one of the two involved door openers has full hands and clearly is at a disadvantage for opening the door. I am speaking of those times when the two people have equal ability and access to opening the door.

Which is it?