After about 3½ years of studying the CBGM, I continue to learn new things about it. Sometimes I discover answers to question I was not even asking. This happened this week while reproducing the textual flow diagrams in my thesis. Because these diagrams connect each witness with their closest potential ancestor (within the constraints set by the user), someone smarter than me might wonder what happens when a witness’s closest potential ancestor is not extant at the point of variation being studied.
Well, I found the answer. When this happens, any descendants are simply left out of the diagram, even if they
are extant at this point.
Let’s give an example. If we look at the textual flow diagrm for the whole Catholic Epistles, we see that 104 is the closest potential ancestor for 1838 and 459. 459, in turn, is the closest ancestor for 1842.
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| 104 and its descendants in the predominant textual flow for the Catholic Epistles |
So, what happens when 104 is not extant? Its three descendants will disappear whenever the diagram is set to connect each witness with its closest potential ancestor (a connectivity of 1). In such cases 1838, 459, and 1842 are not displayed. For example, here is 2 John 1.2/2-6 with a connectivity of 1: You will not find the four witnesses I just mentioned.
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| At 2 John 1.2/2-6 with connectivity set to 1, 104 and its descendants are missing |
But if you change the connectivity to absolute, they all reappear because they can be connected to other potential ancestors which, unlike 104, are extant at this point of variation.
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| At 2 John 1.2/2-6 with connectivity set to absolute, the descendants of 104 reappear |
I think there are probably better ways to handle these situations, such as making the non-extant ancestors gray or circling them with a dashed border. Alternately, the descendants that have no ancestor available could just free float in the diagram.
I suspect this was something that was just overlooked in the original programming. Perhaps the situation will be treated differently in Acts. In any case, it’s worth knowing in case you’re using an absolute connectivity and wondering where some of your witnesses have gone.
