In logic (or philosophy) jargon, what do you call the generalization of the two mutually exclusive condition states
must not? I assume mustness isn't the correct term but it conveys what I'm looking for...
Put differently, how do you call the property of being either a "must" or a "must not" condition.
Perhaps it is easier to start and suffice with the logic term for the group containing the mutually exclusive
not X, or the condition of being/relating to either one of them. I wouldn't call this notness, but you can get the idea of what I'm after...
From analyzing the replies it seems the group I had originally meant should have been defined much more rigorously as comprising the following two states:
- Must have / be / exist / etc...
- Must have not / be not / exist not / etc...
Trying to deconstruct, both the two states are in fact composite structures comprising two elements each: "Must" and a further "Condition".
One state allowed by the group is that condition X must apply, the other allowed group state is that condition X must-not apply. The state that condition X may or may not apply is - not a state allowed by the defined group even though in English saying
must not has the interpretation of may or may not / it doesn't matter. That last interpretation is not included in my group definition.
The two types of conditions are mutually exclusive, but the the two aggregate statuses are not different modalities or a bivalence; the opposite of must can also be "does not have to be", so modality/bivalence are probably ambiguous unlike the group definition, or do not apply as a representative description of the group comprising the two (composite) states.
"necessity type" or "necessity requirement" does not capture the relationship between the "Condition" parts, which I could hope there's a word to describe, but at least it does not imply something out of sync with the group's actual definition.
Or, I could call it "condition modality", if "modality" indeed applies. Again, it won't capture the entire specificity of meaning of the group's content, as this group is a modality that allows just two opposite states and not the broad spectrum of modalities, but at least it does not imply something out of sync with the group's definition.
dichotomous condition modality would capture it all! albeit being a terrible clause to process for most humans, which this question called for anyway ;)