Hello Powerscore and everyone!
This is a question of concept I have been struggling with for some time, I apologize if I become repetitive and for this long explanation. I understand the idea and identification of conditional reasoning as well as the clear cases in which "if" modifies the sufficient and "then" modifies the necessary, but a problem I have had is when it comes to the tense or chronological order of some sentences. What I mean is, in the example used above: "The trees always blossom in May if April rainfall exceeds 5 centimeters." You say that the Necessary condition is "trees blossom in May" and the Sufficient is "In April rainfall exceeds 5 cm". I can initially see that because of where "if" is. But when I read it closer I do not understand how logically it makes sense for the necessary condition to be the occurrence that occurs AFTER the sufficient. In the popular examples, "if you get an A+, then you must have studied" and "if you have a driver's license, then you know you are 16+". But in each of those the necessary condition is always met before the sufficient occurs, "If x happens, then you know the condition of y must have been satisfied before". I understand that well. Yet in this case and in this sentence, we are saying the necessary condition of "trees blossoming in May" must be fulfilled for us to know that it rained over 5cm in the previous month April? It is not the order presented
(i.e. the sufficient condition/"if" coming after the necessary condition) to me that confuses me, it is the fact that a later occurrence in May is necessary for there to have been over 5 cm of rainfall in April. When I initially read that sentence it clearly sounds like "for the trees to blossom in May, rainfall in April must exceed 5 cm/ the occurrence in May will happen, on the required condition
that it rained over 5 cm in the previous month" where the necessary condition is the rainfall in April. Even if you phrase it in the style of assuming the rainfall is sufficient as you did (Sufficient-->Necessary): "If the rainfall in April exceeds 5cm, then we know the trees will always blossom in May" I do not understand how we can then call the blossoming in May a Necessary condition for the rainfall in April to occur, it sounds more like a guaranteed prediction based on what already occurred (the rainfall) or similarly that the exceeding rainfall sounds like what is necessary to occur for the trees to blossom in May. If it was a Necessary condition that means it can happen with or without the rainfall and I understand how it could, but the sufficient (the rainfall in April) can only happen if the trees blossom a month later in May? That does not make logical sense to me.
The sentence makes it seem like the rainfall is what must happen to cause/causes the blossoming. Is it not saying if it rains this much, with that necessary occurrence we can then guarantee that the future blossoming occurrence in May will occur which could not happen without the exceeding rainfall?
Another similar confusing example is in the On Demand coursebook Lesson 2 pg 9, the first example says "If it rains on Tuesday, then we will go see a movie". I get that because of the "if" and "then" placements, movie is the necessary condition. But I do not understand how logically for it to rain, it is necessary for us to go see a movie i.e. us going to a movie MUST occur for it to rain. Does us watching a movie allow for the rain to occur and that it cannot rain on Tuesday without us satisfying the condition of going to see a movie?
It sounds as if the rain happens first, and then the movie because of the tense of "then we will go", if this happens, then (indicating the next event follows) we will go to see a movie. I would understand if like the studying example it said "If it rains on Tuesday, then we WOULD HAVE/WENT to see a movie, indicating the necessary already occurred and was satisfied. But that is not how the sentence is worded.
What I generally mean is sometimes the use of "if" and/or the chronological tense of the events, sounds like the sentence modified by "if" is the necessary i.e. "x will happen if y happens" is the same as "x will happen on the condition that y happens" where y sounds like the necessary condition that must occur for x to occur even though it is modified by "if".
I apologize if what I said was confusing and too long, I would be happy to clarify it in any way. Any help with this would be greatly appreciated! Thank you!