Bottom-up construction of ontologies

We present a particular way of building ontologies that proceeds in a bottom-up fashion.Concepts are defined in a way that mirrors the way their instances are composed out of smaller objects. The smaller objects themselves may also be modeled as being composed.Bottom-up ontologies are flexible through the use of implicit,and hence parsimonious, part-whole and subconcept-superconcept relations. The bottom-up method complements current practice,where as a rule ontologies are built top-down. The design method is illustrated by an example involving ontologies of pure substances at several levels of detail. It is not claimed that bottom-up construction is a generally valid recipe; indeed, such recipes are deemed uninformative or impossible. Rather,the approach is intended to enrich the ontology developer’s toolkit.