Editing Philosophical Research:Data model (section)

== Ontological-category Items ==

=== S0 Concepts ===

logical or metaphysical categories which group Z or S items

=== Z0 Physical Patterns ===

Z0 Patterns represent generic versions of Z Items which one can expect to be instantiated as some kind of spacetime-unique object or identifiable instance. For example, one Z0 Item could conceivably be "cat of species <i>Felis catus</i>", and its corresponding Z/Z1 Item could be a highly notable individual cat, while at the same time, Items in the S dimension mirror this Z0-to-Z1 relationship with the S0 Item "fictional cat" and the S1 Item "Graystripe". Equally, a Z Item could be used to mark a real-world phenomenon which seemingly cannot be generalized despite recurring often, such as a Z Item for "quantum mechanics (study)". Despite there being many papers about quantum mechanics, there is not necessarily any such thing as a drop-in replacement through the study of some different kind of physics. Even so, there could still conceivably be a Z0 Pattern for "academic study of physics" which instantiates itself as "quantum mechanics (study)" and "thermodynamics (study)".

=== Other kinds of "zero" categories ===

It is unlikely, though maybe possible, for there to be more "0" categories introduced. "M0" is a potential candidate, for some sort of generic repeatable category of questions that keeps instantiating itself into new versions of a particular kind of question. One possible example of an M0 Item is "National questions"; in concept, every group of people that eventually becomes a nation-state has a national question.

There are no F0 Concepts because of the way in which the inherently arbitrary nature of some S0 classifications for S1 or S2 Items makes it impossible to identify "objectively wrong" categories. At one point an "H0" category was considered for historically-contingent grouping objects that have no particular rationale for why they are the way they are today, but with time this was simply flattened back into "Z".