When we talk about Internet scale naming. You'd better include time in the scale. We need URL's plus time-stamping. Times come from a namespace - changes over the time. Santa Claus is a well known name for an entity that does not exist.
Abstract concept is a list.
More from reference than the actually document. WWW is referencing less and less on the web. There are references to names that don't exist. There is a fundamental incentive for doing so.