The crux of it is (quoted from Wildcard):

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` A B if A then B`

True True True

True False False

False True N/A (therefore, True)

False False N/A (therefore, True)

N/A (therefore, True) is, afaict, arbitrary. I assume it was adopted as a convention to make certain logical things "neat", in the same manner that 1 is prime (or isn't prime, I forget which).

Anyway... there are two different relations to look at: (note: {} is not intended as set notation)

One is:

{set of (A's truth value AND B's truth value)} -> A {relation} B

The other is:

A {relation} B -> {set of (A's truth value AND B's truth value)}

where {relation} could be either of "implies", "is consistent with", "if..then" and the question becomes what to do with "unknown".

"If it's raining, then there are clouds".

"It's not raining".

Are there clouds? Unknown. Not-raining and clouds are "consistent with each other". They are possible, but not required.

Yakk wrote:i do not see how "is consistent with" helps in any shape or form in this discussion. It is not a drop in for implies anywhere I can see

No, it is not a drop-in for implies. It has a different meaning, one which I contend is a better English translation for the logical "implies" truth table, where N/A is defaulted to TRUE.

So, in the evolution of logic, why was N/A defaulted to TRUE?

Jose