Halliday & Matthiessen (1999: 83, 85):
Delicacy is a uniform ordering from most general to most delicate; but along this scale, semantic systems differ both in the number of distinctions at any one degree of delicacy and in the overall delicacy that is achieved. There are specific differences associated with particular taxonomic regions. For instance, humans and higher animals are much more highly elaborated than lower animals. But there are also general differences in the nature and degree of taxonomic elaboration associated with different 'bands' in delicacy. Such general taxonomic principles are probably best known for folk-taxonomies in the domains of plants and animals, diseases, and the like (e.g., Berlin, Breedlove & Raven, 1973; Conklin, 1962; Frake, 1962; Slaughter, 1986); these fall within 'element: participant: thing' in the ideation base. The maximum steps in delicacy in a folk taxonomy are kingdom (unique beginner), life form, basic (generic) level, specific level, and varietal level. These steps are by no means always present in every particular taxonomy; and they have different characteristics, summarised in Table 2(6) (for taxonomic examples, see Leech, 1974).
