The answer to your dilemma, Jessica, is to go clockwise. When you have a conditional premise and a conditional conclusion, and they share one term (either the sufficient conditions are the same or else the necessary conditions are the same), you can justify, or strengthen, or identify an assumption, by connecting the two different (rogue, we sometimes say) conditions with a conditional arrow that points in a clockwise direction, like so:
P: A B
C: A C
Connect these two by making B sufficient for C:
B C (and you can imagine that arrow is pointing down from the upper right to the lower right side of the original layout; in other words, it's pointing in a clockwise direction)
Or you may be faced with this:
P: A B
C: C B
Connect these two with an arrow that makes C sufficient for A:
C A (and again, imagine this arrow pointing in a clockwise direction, from bottom left to top left)
As long as you are placing your premise in the top and your conclusion on the bottom, "go clockwise" will always work!
Try that out a few times and see if it makes sense to you. Good luck! Go clockwise!
#18- Columnist: Taking a strong position on an
Hi everyone, thank you for all the explanations on this post. I have a few questions. First, I was wondering about the diagramming of the question. I thought that "is required/is necessary/it is essential to" introduce sufficient statements. Expertise requires practice (E--> P) and practice is required to have expertise (E-->P) diagram the same statement. And in the LR bible's chapter on conditional reasoning i see that "in order to" introduces a premise. So I wasn't sure how to diagram sentence 2 from the stimulus. Can a segment of the sentence be both a premise and a necessary condition? ("in order to understand an issue fully" introduces the premise but it is a necessary condition because the second half of the sentence "it is essential to" introduces the sufficient statement).
I initially chose A (i tried to do the problem without diagramming), but then the way I approached the stimulus the second time was by labeling the first sentence as background info. The second sentence as the premise and the third sentence as the conclusion.
I diagrammed as the following:
Premise: consider evidence impartially--> understand an issue fully
Conclusion: strong position--> consider impartially
the chained link would be: strong position--> (consider evidence impartially)-->understand fully
contrapositive would then be: don't understand fully--> don't take a strong position.
I get C even though I flipped the premise so I am not sure how this diagramming is incorrect and differs from the powerscore staff's diagramming but we get the same answer.
I also looked at the stimulus and underlined the "issues": "understand an issue fully" "consider evidence impartially" "not take a strong position" and "consider evidence impartially"
Consider evidence impartially appears twice- in the premise and the conclusion so the answer/principle must involve linking "understanding an issue" and "not taking a strong position".
When going through the answer choices
A) can we get rid of A because the stimulus does not mention anything being reasonable and by saying we should or should not do something does not by default mean that it would be reasonable to do so? Conditionality only infers what will or won't happen under certain circumstances but we cannot put opinions on it. It could very well be shameful or unreasonable to do what the chained link stipulates, it is not for us to have an opinion on the link, only to infer what is being said?
B) mentions strong position but does not mention understanding the position fully
C) mentions understanding an issue and taking a strong position, keep
D) mentions understanding an issue fully but does not mention taking a strong position
E) I have the same skepticism as with A in saying that it would be "reasonable" to do something just because we said we should not do something else. Also, this mentions strong position but does not mention understanding a position fully.
I know I have several questions nestled through this post so thank you in advance for your help!!
There is a lot going on here, hasan, but I think a short answer might suffice: "is essential/is necessary/is required" introduces a NECESSARY condition, not a sufficient condition. If something is essential, then it is required.
Also, "premise" and "sufficient condition" are not synonymous. A conditional claim in it's entirety can be a premise, as can a necessary condition. A premise is just a claim that is intended to support another claim in an argument. Here's what I mean:
"If we get a new puppy, our old dog will start acting young again. Our old dog has started acting young again, so we must have gotten a puppy."
Premise: If we get a new puppy, our old dog will start acting young again (that entire conditional claim, with a sufficient condition and a necessary condition, is a premise)
Premise: Our old dog is acting young again (a necessary condition from the prior premise)
Conclusion: We must have gotten a puppy (the sufficient condition from the first premise)
You can probably see that this is a bad argument because it is a Mistaken Reversal.
Take another look at this stimulus with the understanding that "is essential" means "is a necessary condition," and see if it makes more sense to you now. Let us know if that clears it up!
I'm still confused. In the following post answering a different question, Claire Horan shows how "is essential to" introduces the sufficient. When you diagram, "the ability to trust others people is essential to happiness" as Claire produces below, you get H--> T. This strengthens what I had diagrammed earlier where "is essential to" precedes the sufficient clause.
This is from: Home ‹ LSAT Preparation ‹ LSAT Logical Reasoning ‹ PrepTest 56 - December 2008 - LSAT Answers and Explanations - LR ‹ Section 3 Question 16:
Below is copied from Claire Horan's post:
"The ability to trust other people is essential to happiness" should be written as:
You have happiness You have ability to trust
You know this because "essential" and "necessary" are the same thing, and we write these as sufficient necessary.
The contrapositive is: no ability to trust no happiness
This part is the therapist's conclusion. We know that because of the word "for" before the premise.
That's absolutely correct, and consistent with my explanation , hasan. There is an important difference between "is essential" and "is essential to", and that is the inclusion of the word "to". Ask yourself, in each of these statements, what is the thing that is essential? That is the necessary condition:
1. When you love someone, trust is essential
2. Happiness is essential to trust
In the first case, trust is the essential thing. In the second, however, happiness is the thing that is essential. The first would be diagrammed as Love Trust, while the second would be Trust Happiness.
That is a sneaky, minor but important difference! The addition of "to" makes it sufficient, that distinction was tripping me up, thank you for clarifying! Makes much more sense now.