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Before we talk about this slide, let me say that...

Disclosure of how subject-sameness is detected also facilitates the merging of diverse topic maps, with diverse topic map ontologies. On the basis of the disclosures of diverse Topic Map Applications, one or more "encompassing" Topic Map Applications can be designed that can cause subject reifiers to be recognized as reifying the same subject, even when they had no properties in common. The result such a merged topic will have multiple subject identity properties, each of which remains as potent, in its own Topic Map Application (its own universe of discourse) as it was before.

Indeed, when reifiers merge, there need not be any information loss. For each property that it defines, a Topic Map Application must disclose how to calculate the value of the merger of two of them. This process can, of course, be lossy, but it need not be.

OK, so now to this cookbook slide that tells us how to merge ontologically diverse topic maps.

Maybe the Coolest Thing About Conferred Properties is...

Ontologically diverse topic maps can be merged.

1. A Topic Map Application can be defined whose worldview "encompasses" the worldviews reflected in the diverse Topic Map Application. Its universe of discourse is big enough to intersect their universes of discourse.
2. The encompassing Topic Map Application can require that the values of the properties it defines be conferred on them based on the values of the properties of the reifiers of the diverse topic maps -- properties defined by their respective diverse ontologies.
3. More specifically, the encompassing Topic Map Application can define Subject Identity Properties, and it can confer values on them that will cause reifiers governed by diverse Topic Map Applications to merge.

When a single merged reifier has multiple Subject Identity Properties defined by multiple diverse ontologies, it acts as a "wormhole" between universes of discourse. Its subject appears in multiple universes, in their respective diverse terms. Users can exploit multiple universes from a single vantage point -- a single reifier.