The goal of this article is to assist designers, researchers, professional analysts, procurement officers, educators, and students in evaluating and creating visual analysis tools. We present a taxonomy of interactive dynamics that contribute to successful analytic dialogues. The taxonomy consists of 12 task types grouped into three high-level categories, as shown in table 1: (1) data and view specification (visualize, filter, sort, and derive); (2) view manipulation (select, navigate, coordinate, and organize); and (3) analysis process and provenance (record, annotate, share, and guide). These categories incorporate the critical tasks that enable iterative visual analysis, including visualization creation, interactive querying, multiview coordination, history, and collaboration. Validating and evolving this taxonomy is a community project that proceeds through feedback, critique, and refinement.

... any idea of what an instance could be?

Looking closely at http://id.loc.gov/vocabulary/iso639-1/fr for the first
time seriously (shame on me, can't even tell since when this URI has been
available) ...
I read that it is a *rdfs:subClassOf*
http://id.loc.gov/vocabulary/iso639-1/iso639-1_Language

Well, why isn't it an *instance* of this class?
I can see the rationale : there is not "one" French language, one can
imagine further subclasses such as Canadian French, Middle-Age French etc.
so French is a class of languages OK.
But are there any subclasses of French defined at id.loc.gov ?

And if it were the case, where do one stop the subclasses recursion and
introduce instances, if any? Is it turtles all the way down?

The Netflix genre taxonomy.

We are, all of us, abandoning taxonomy, the ordering and naming of life. We are willfully becoming poor J.B.R., losing the ability to order and name and therefore losing a connection to and a place in the living world.

This two-part article is a step-by-step guide for those wishing to create new taxonomies for their business unit, or client. It will outline the many different elements that make up a quality taxonomy and the pitfalls you should be aware of when starting a new project.