Sadly, the people at whom this sign is aimed will be too engrossed in their newsfeeds to even look up and see it. It was agreed upon long ago that the average speed limit of urban walking would be a light, hostile sprint. Your effort to update Facebook while walking breaks the stride of everyone behind you, leading them all to pray that God unfriends you from life. See below for more public transit etiquette signs from street artist Jason Snells' series designed to create a less infuriating commute.