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R117 / 1:1c

Subclass defines subset on a side of zero or one Minimal Partition

Minimal Partition yields subset on a side as exactly one [[Subclass]

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A Minimal Partition splits the set abstracted by the Superclass into two proper subsets arbitrarily designated as A and B, each of which corresponds to some Subclass in the same Generalization.

A Subclass may be on the A side of the Minimal Partition, on the B side or neither. If neither, then there must be at least three Subclasses in the Generalization.

Formalization

Minimal Partition.(Rnum, Domain, A subclass) -> Subclass.(Rnum, Domain, Class)