Thanks for the message. I'm glad we've been able to help you out so far! Let's take a look at your question and see if we can sort this out for you.
From the looks of it, you've gotten tripped up on what is a very tricky point. In answer choice (A), the argument tries to conclude that a sufficient condition has occurred. In the "What you can conclude" segment, the sentence you referred to reads, "If
the sufficient condition has been met..." (italics added). That's a big difference there, because in (A), they don't state factually that the sufficient condition has been met, and then conclude the necessary occurred; instead in (A) they factually state that the necessary has occurred and then attempt to conclude that the sufficient has occurred. In other words, they have it backwards.
With the above in mind, let's go back to the stimulus as well as answer choice (A). The relevant principle in the stimulus appears as:
Statement true + Made without intended deception
What the guidelines say on page 492 is that if
you know that Ted's statement is wholly truthful, then
you know that Statement true + Made without intended deception. But that's not how (A) works. What (A) does instead is that it tells you, "After all, Ted was not trying to deceive the investigator." In other words, you know that Ted's statement was "Made without intended deception." If you know that this necessary condition occurred, does that allow you to then conclude that the sufficient condition occurred (namely that his statement was wholly truthful)? No, you can't do that because it would be a Mistaken Reversal (note: for the sake of clarity, I'm going to ignore the fact that it appears that Ted's statement may not, in fact, be true; I don't think that particular point is what is causing you confusion here).
Let's step back a bit further and simplify this to see if we can make this conditional issue even clearer. Let's assume for a moment that you have a principle that reads A
B. If someone makes a valid argument using that principle, they'll treat it as a premise, and then add a second premise to that principle in order to draw a conclusion. Here are some examples:
- Premise: A B
What happened? We took the principle, added in the fact that the sufficient condition had occurred, and that allowed us to draw the conclusion that the necessary condition must have occurred. This is what we call a restatement of the conditional principle.
Premise: A B
What happened? We took the principle, added in the fact that the necessary condition did not occur, and that allowed us to draw the conclusion that the sufficient condition did not occur. This is a contrapositive.
Ok, both of the above are pretty standard valid argument forms. Notice how we either use the occurrence of a sufficient condition as a premise, or the non-occurrence of a necessary condition as a premise, in order to draw conclusions. The point on pages 492-493 is that there's no argument form that allows you to use a conditional principle to conclude
that the sufficient condition in that principle occurred. They could tell you as a second premise that it occurred, but you can't draw the conclusion that the sufficient condition occurred. That premise/conclusion issue may look like a small difference, but as you can see it's actually huge
As a result, that means this form doesn't work:
- Premise: A B
There's no second premise here that you can add to A B to then conclude that A occurred. Yet, that's what answer choice (A) is attempting to do (and that's what Mistaken Reversals attempt to do), and from a conditional standpoint you can't draw that conclusion. You also can't draw the conclusion that a necessary condition does not occur (this is point 2 on page 493).
The reason this discussion is there is that in Principle questions that use conditional reasoning, this is a common thing they've done over the years in wrong answers. Once you've seen an answer like (A) few times and understood it, the next time you see it you can cast it aside quickly and efficiently, with no confusion.
Ok, on to your question about whether "necessary conditions considered the conclusions in conditional statements?" As you can tell from the discussion above, what is a premise and what is a conclusion is a crucial part of understanding what is going on. Not being perfectly clear on this relationship is likely the underlying issue in the problem you had with (A) (and it is why I focused on this portion of why (A) is wrong, and bypassed the "statement is true" portion). The short answer to whether necessary conditions are considered conclusions in conditional statements is that it changes depending on the argument form. Let's go back and look at the two examples I posted above to make this clear:
- Premise: A B
Here the necessary condition--by itself--ends up as the conclusion. So the answer in this case is yes.
Premise: A B
Here the negation of sufficient condition ends up as the conclusion. So the answer in this case is no.
As you can see just from these two cases, it depends on how the argument is organized and what other premises you are given. That's what the text on pages 492-493 is driving at, and so it is critical that you understand the meaning behind that discussion.
These concepts do come up earlier in the book, so let me also refer you back to pages 116-119 in the book for review. You may also find this recent article
I posted helpful in understanding how the premise/conclusion aspect works in conditionality.
Please let me know if this helps. Thanks!