cwconrad wrote:The validity of the apodosis necessarily depends on the validity of the protasis. If the protasis is false, then the apodosis must also be false.
Hmm are you referring only to the two conditional statements that Peter brought up? If so, then I see your point, though I've a slightly different understanding which I will mention later below. I'd be glad to hear what you think!
Meanwhile I thought it might be useful to look at what the conditional in general means. In my view, without the context it is a purely logical one; "If the condition holds, the conclusion must hold" which is equivalent to "If the conclusion is not to hold, then the condition must not hold.". In particular the conditional does not assert anything in the case that the condition does not hold or in the case that the conclusion is to hold. For example:
[Matt 15:14] ... τυφλος δε τυφλον εαν οδηγη αμφοτεροι εις βοθυνον πεσουνται (Certainly people may fall into ditches even if they are not blind led by blind.)
[Luke 22:68 Byz] εαν δε και ερωτησω ου μη αποκριθητε μοι η απολυσητε (Surely his captors would not release him if he doesn't ask anything.)
Also, in the case where the conclusion refers to something whose existence is specified in the condition, then that quantification is automatically understood to be further universally quantified so that it encompasses both the condition and conclusion. Most language users do not notice the way they interpret such statements with referents, hence they may find my expansions below strange, but this automatic universal quantification would explain not only such conditionals but also many normal statements including predicative constructions. For example:
[Mark 3:24] ... εαν βασιλεια εφ εαυτην μερισθη ου δυναται σταθηναι η βασιλεια εκεινη
= ... whichever kingdom it is, if it is divided upon itself, it cannot stand
[Mark 13:21] ... εαν τις υμιν ειπη ιδου ωδε ο χριστος η ιδου εκει μη πιστευετε
= ... for anything that anyone says to you, if it is "Behold, here is the Christ." or "Behold, there.", do not believe it
[John 9:22] ... ινα εαν τις αυτον ομολογηση χριστον αποσυναγωγος γενηται
= ... that whoever it is, if he confesses that Jesus is Christ, he is to be cast out of the synagogue
Like the above examples, under the universal quantification, if the condition does not hold, nothing is asserted about whether the conclusion holds. On the other hand, the equivalence I gave at the beginning will still be true here even if the conclusion is not a declarative statement. To see why, note that they could be rephrased as follows:
[Mark 3:24] ... whichever kingdom it is, if it is to be able to stand, it must not be divided upon itself
/ ... if a kingdom is able to stand, it must not be divided upon itself
[Mark 13:21] ... for anything that anyone says to you, if you believe it, it had better not be "Behold, here is the Christ." or "Behold, there."
/ ... if you believe something that someone says to you, it had better not be "Behold, here is the Christ." or "Behold, there."
[John 9:22] ... that whoever it is, if he is not to be cast out of the synagogue, he must not confess that Jesus is Christ
/ ... that if anyone is not to be cast out of the synagogue, he must not confess that Jesus is Christ
A typical use of the conditional statement "If X, then Y" is to imply "To avoid Y, you cannot have X", but it does not affirm that without "X" you will successfully avoid "Y". Of the above examples this applies to Matt 15:14, Mark 3:24, John 9:22.
However, in many cases the context will indeed result in the conditional implying more than its logical meaning. For example, another typical use of the same conditional statement "If X, then Y" is to imply beyond its logical meaning that "If not X, then you cannot expect Y". Even in such usages, it is often still the case that the conditional statement is not the same as asserting the equivalence of "X" and "Y" (even expectations can be wrong), but the point usually being made is just "X guarantees Y". This applies to instances like John 6:51, 8:36.
When equivalence is desired, writers often use two separate statements that essentially assert "If X, then Y" and "If not X, then not Y", such as in Matt 6:14-15, Luke 10:6, 11:19-20, John 11:9-10. With only one stated, the context may of course suggest an intended equivalence, but I am inclined to think that it is rarely intended to be an exact equivalence.
Concerning those two instances that Peter brought up, I don't see them individually as being statements of equivalence, but together as a pair they essentially do what I described in the previous paragraph, because keeping someone's word is essentially the opposite of persecuting him, and for Jesus and his disciples as recounted in John, nearly everyone eventually took a side.
Anyway, Peter, I too have never learnt to classify conditionals, as I see the same underlying logical meaning in all of them, so I can't help there either.
