Martin (1992: 308):
One way of resolving the question of how taxonomic distance affects cohesion is to make use of IDENTIFICATION and test items to see whether they are experientially close enough for one to have been presumed by the other. Along these lines, the flower straightforwardly presumes a rose, as the insect presumes a mosquito. Hyponyms do not directly presume their superordinates, but they may presume them indirectly through bridging. The reason for this difference is that superordinates contain less information than their hyponyms, while hyponyms encode all of the experiential meaning of their superordinates. This asymmetry is reflected in definitions:
Blogger Comments:rose a beautiful & usually fragrant flower usually of red or yellow or white
[1] This continues the confusion of grammatical reference and lexical cohesion, as previously explained here.
[2] Whether the reference item the in the flower presumes that the identity ('which flower?') is recoverable in a rose depends crucially on the co-text. On the other hand, what is straightforward is the hyponymic relation between flower and rose.
Likewise, whether the reference item the in the insect presumes that the identity ('which insect?') is recoverable in a mosquito depends crucially on the co-text. On the other hand, what is straightforward is the hyponymic relation between insect and mosquito.
[3] In SFL theory, lexically cohesive hyponymic relations do not involve presumption.
[4] The relation between superordinates and hyponyms is delicacy. Superordinates are more general (broader) categories, hyponyms are more specific (narrower) categories.
[5] In terms of the SFL theoretical architecture, hyponymy combines (logical) elaboration with (experiential) attribution. Accordingly, there is no encoding in hyponymy, because encoding is a direction of coding in identifying relations. The experiential relation between hyponym and superordinate is class membership, not identity.
[6] Any informational asymmetry in the attributive relation between hyponyms and superordinates (Carriers and Attributes) is not "reflected" in the identifying relation between words and meanings (Tokens and Values).
