Resource Edge Cases: Combination, Cross-Category, and Distinguishing Resources

Three named exceptions handle resources that don’t sit cleanly in one category or classification.

Combination Resource applies when a single real-world resource is made of parts from more than one resource category. A book is the clearest case: the paper and ink are Equipment (B), but the information printed on the pages is Information (C) — and the book is classified as C, because the content is what determines how it’s used, not the physical medium carrying it. A bag of potato chips works the same way: the bag is a constituent Equipment resource, the chips are an Energy resource, and the whole thing is classified as Energy, because its nutritional qualities — not its packaging — determine its use.

Cross-Category Resource applies when a single resource changes category as a result of being incorporated into something else, rather than being made of multiple categories at once. Loose bricks are Equipment (B) — they’re not yet fixed in place. Once installed into a wall, they become Physical Space (A), because part of the definition of an A resource is that it’s fixed in place. It isn’t that the building has both A and B components; it’s that the bricks themselves have become A resources.

Distinguishing Resource is a different kind of exception, living in work loci rather than resource classification: a syntactic category for when a subject resource is the specific factor that separates two otherwise identical activities. A postal service and a satellite network both perform the same 1.2.2 activity — transporting information — but the postal service does it by truck (a B resource) while the network does it electronically (an A resource). The distinguishing resource is what lets the same activity code capture that real difference.

All three exist for the same underlying reason: the Locus Model classifies by function and use, not by physical composition — an apple sold as a snack and an apple baked into a pie are, materially, the same object, but the Locus Model can classify them differently because they’re being used differently.

See also: Constituent Resource vs. Final Resource · Resource Stage and Substage

Part of Activities & Resources: The Grammar, course 2 of 7 in the Locus Theory series. For the full term-by-term specification, see the Lexicon.

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