Comment by elijahwright

Mmhmm. A talented cataloger in a research library understands where the 'fuzz' in these systems is - where the margins intersect - and they have a process for helping systematize those classifications in a way that they can socialize with other librarians across the world. (If nobody has ever cataloged a particular book before... your record is probably going into OCLC WorldCat and other people will borrow the output of your thinking process later... making things more and more definitive.)