2.12 The commodity root taxonomy consists of two subtypes: elementary commodities and composite commodities.

Figure 5 - Top level ontology of commodities

1. On the next section, proposition 2.13 defines the subtype of elementary commodities as an extension.

Proposition 2.14 defines the subtype of composite commodities in terms of intention.

2. A commodity is either elementary or composite.

By distinguishing between elementary and composite commodities, the set of commodities is completely partitioned into two subtypes. This is a first step in establishing the ontology of commodities.