I couldn't resist taking a picture of the instructions posted on the door of the Children's Museum of the Danish Nationalmuseet. First, I enjoyed the incorporation of green means ok, yellow is a caution, and red means prohibited. In particular, I enjoyed that the green tells you to "travel through time, and Have fun with history".
I am not entirely sure if this suggests that the Danes need to be told when and where to have fun or to liven up their lives a bit, but I will leave that to the sociologists. This reminds me of some of the messages I have seen on TriMet buses in Portland, where they try to use positive messages as opposed to restrictive or strict prohibitions. No loud music is transformed to use headphones when listening to music. I especially appreciate TriMet's "Repsect the Ride" message.
This makes me think about whether we should try to incorporate this more into the City of Portland and in on-street parking. Taking a customer's viewpoint, what do I want to be asked to do (instead of told to do), might offer a way to lay out the welcome mat.