d a relation classification
infomorphism between the relation classifications of source and target.
The context of models <span
 style="font-family: arial; font-weight: bold;">Model</span> consists
of models and their infomorphisms. The
classification of relations, along with the abstractness of tuples, is
used to show the existence of free models (and logics). The subset
construction on entities and relations defines a free power model
passage <span style="font-family: script mt bold;">P</span>
: <span sty