I prefer to think of the distinction as fluid. What one application considers metadata is another application's data. From the apparently trivial (file sizes,

I prefer to think of the distinction as fluid. What one application considers metadata is another application's data. From the apparently trivial (file sizes, line numbers) to the domain specific (date of joining social network; file server cluster that hosts this image), each tool doing the work has a very different viewpoint. The motivation for abandoning the distinction is this fluidity, not that there is no distinction. (Sidenote: I like the Clojure definition of metadata: "It is used to convey information to the compiler about types, but can also be used by application developers for many purposes, annotating data sources, policy etc. "An important thing to understand about metadata is that it is not considered to be part of the value of an object. As such, metadata does not impact equality (or hash codes). Two objects that differ only in metadata are equal.")