Without getting in to too much ontological detail, it should be noted that Smith's approach to ontology is not universally accepted (especially on universals :-). See the article by Merrill, the response by Smith and Ceuster, and the rebuttal by Merill in the journal of Applied Ontology last year - I think all three articles are still open access: <a href="http://iospress.metapress.com/content/j3324564p5l33863/?p=94dfb401906b427a8b3e9f91406128f6&pi=0">http://iospress.metapress.com/content/j3324564p5l33863/?p=94dfb401906b427a8b3e9f91406128f6&pi=0</a> <a href="http://iospress.metapress.com/content/1551884412214u67/?p=5087b84fdd9647348fbbaaaa5c6b6be3&pi=0">http://iospress.metapress.com/content/1551884412214u67/?p=5087b84fdd9647348fbbaaaa5c6b6be3&pi=0</a> <a href="http://iospress.metapress.com/content/21l17015v46687v0/?p=f181b3ce180b482fab3299b204343ab6&pi=1">http://iospress.metapress.com/content/21l17015v46687v0/?p=f181b3ce180b482fab3299b204343ab6&pi=1</a> For a different approach, see e.g. Cyc's use of the concept of substances (which find parallels in [count-] nouns). Tutorial slides: <a href="http://www.cyc.com/doc/tut/ppoint/SpatialPropertiesAndRelations_files/v3_document.htm">http://www.cyc.com/doc/tut/ppoint/SpatialPropertiesAndRelations_files/v3_document.htm</a> Parts: <a href="http://www.cyc.com/cycdoc/vocab/part-vocab.html">http://www.cyc.com/cycdoc/vocab/part-vocab.html</a> Substances: <a href="http://www.cyc.com/cycdoc/vocab/composition-vocab.html">http://www.cyc.com/cycdoc/vocab/composition-vocab.html</a> Spatial relationships: <a href="http://www.cyc.com/cycdoc/vocab/spatial-vocab.html">http://www.cyc.com/cycdoc/vocab/spatial-vocab.html</a> Cnl relevance: cyc can help with disambiguation - <a href="http://en.scientificcommons.org/42859738">http://en.scientificcommons.org/42859738</a> ACE wins from micro-theory like ontologies too: <a href="http://valoda.ailab.lv/cnl/cnl2009.pdf">http://valoda.ailab.lv/cnl/cnl2009.pdf</a> Simon