Taxonomy is a form of classifcation used to order the Natural World, based on a hierarchy using subsumptive realtions: Domain Phylum or Division Subphylum or subdivision Class Subclass Order Suborder Family Subfamily Genus --------------------- Species In terms of our analysis of 5 Worlds, we see that although the objects of taxonomy are in the natural world; most of the categories of taxonomy belong to the mental world because they deal with universals rather than particulars of individual plants. Library of Congress Taxonomy, Animal > Animals Classification Taxonomy (Biology) Taxonomy, Cladistic Taxonomy, Immunological Taxonomy, Numerical Taxonomy of educational objectives Taxonomy, Phylogenetic Taxonomy, Plant Taxonomy, Quantitative > Numerical taxonomy