I have to admit to some rather uncharitable feelings when I can’t park within sight of a supermarket because all the near-the-doors spaces have been filled by wheelchair users and parents with prams.
What happens, I wonder, if you happen to be a young parent in a wheelchair -do you have parking precedence over eg a disabled senior citizen? Today’s invention is a way to express this hierarchy fairly as a two dimensional car parking map: a Venn diagram on tarmac.
I assume that there are, say, five equally important categories of parking privilege: eg senior(S), with children(C), wheelchair(W), VIP(V) and loyal customer(L). People who are in the conjunction SCV will need to be closer to the store than those in SC, for example. Those in CWV will be at the same distance as CVL. Each of these conjunctions within the Venn diagram for five overlapping sets is represented as a disc of a different colour. The red disc represents those people who are members of all five sets (with the store located at the centre of this disc). Each different coloured disc represents a different conjunction of privileges, providing all possible combinations with a disc-shaped parking region at a distance from the store roughly inversely proportional to the number of categories it stands for. The greenish circles represent parking spaces for people who fall into two categories at once, whereas the blue circles stand for people who have only one privilege attribute.
It’s possible to adapt this picture for more or fewer categories, of course, and to adjust the total area for discs of each different hue (eg blue or green) to the local demographics.