Kastalia is composed of "knots" which have attributes and relations ("bounds") to other "knots".

Everything (e.g. user, institution, event, presentation slide, fairy tale, musical piece) is a knot.

A knot is a "Ding an sich". 

Bounds are predicated. (hello sir Berners-Lee, hello Wikibase, hello "semantic web")

A knot is presented to an observer (e.g. human user) by means of a template.

Combination of a knot, other knots which are bound to it and a template yield "Ding für uns".