SBVR16 — Correct the scope of placeholder terms

In SBVR clause 8.3.4, in the entry for ‘placeholder’, it is stated that a placeholder exists in only one verb concept wording, and it refers to some role of the verb concept in that wording. It follows that the two placeholders spelled ‘concept1’ in ‘concept1 specializes concept2’ and in the Synonymous form: ‘concept2 generalizes concept1’ (in 8.1.1.1) refer to two roles of the verb concept being defined. Since these two placeholders spelled ‘concept1’ are different designations, how are they related?

Annex C.3.1 does not say anything about the relationship between placeholders in the primary verb concept wording and placeholders in synonymous forms. (It just says something about subscripts being used to differentiate placeholders.) The intent is that the placeholder expression represents the SAME verb concept role in ALL primary and synonymous forms. That is, the placeholder is the SAME DESIGNATION in all verb concept wordings for the same verb concept. The text of 8.3.4 contradicts this intent, saying that the placeholder only has meaning within a given verb concept wording. If the text is correct, it is necessary to state some rule about the meaning of the same placeholder expression (the distinct designation) in the different synonymous forms.

Further, in the Definition of ‘concept1 specifies concept2’, the expression ‘concept1’ appears. Since that expression only refers to a verb concept role within a verb concept wording, it is utterly meaningless in the Definition! There are no placeholders in a Definition, and ‘concept1’ is not a signifier for any concept. And yet, the intent is that ‘concept1’ in the Definition is the placeholder expression and is intended to be interpreted as a reference to the thing that plays that verb concept role in an actuality of ‘concept1 specializes concept2’. Annex C says nothing about the use of placeholder expressions in Definitions, and 8.3.4 makes these usages meaningless, but they appear in every verb concept definition in SBVR.

It appears that the real intent is that a placeholder expression refers to one and the same verb concept role throughout the terminological entry for the verb concept, including at least all synonymous forms and definitions. Whether it also refers to the verb concept role in embedded Necessities needs to be clarified (it is not clear that SBVR ever assumes that, but DTV apparently does). The only aspect of a placeholder that is specific to a given verb concept wording is the ‘starting character position’, which suggests only that that relationship should be ternary, i.e., placeholder has starting character position in verb concept wording.