Nikki - in real time, I would never be able to get the two ( #18 and 24) LR q's that you referenced above. It took me close to an hour just to unpack both questions. I had never seen anything like either before in any previous exam. Could you simplify or break down the structure for either of them so that the next time we are unfortunate enough to come across them, we can more readily recognize them? Thanks for the recap and for your time.
Thanks for the question! Let's take a look at Question #18 first.
The stimulus contains an argument, and – as always – simplification is key. The author does not buy the rumor that patients can predict sudden changes in their medical status. Why is she so skeptical? Because she considers the rumor to be analogous to another, already disproven rumor, namely, that there are more babies born during full moons than at other times. The author points out that there is no correlation between busy maternity wards and full moons; the reason why we think there is one is that the busy nights with full moons are more memorable that the busy nights without them! In other words, a memorable coincidence creates an illusion that something special is actually happening.
Is the same illusory perception affecting our belief that patients can predict sudden changes in their medical status? The author assumes as much. The analogy can only pass muster if we assume that a patient’s correctly predicting a change in his medical status (a memorable coincidence) is more likely to be remembered by the medical staff than if the prediction wasn't correct, and no change occurred. Just like the medical staff is more likely to remember the busy nights with full moons, they should also be more likely to remember when the patient correctly predicts a change in his medical status. For the two rumors to be analogous, we need to assume that in both of them a memorable coincidence creates an illusion that is ultimately untrue.
This prephrase agrees with answer choice (B), which states that a patient’s prediction is less likely to be remembered if no change occurs (i.e. the prediction is inaccurate). The corollary to this statement is that a patient’s prediction is more likely to be remembered if it actually proves true. This is precisely what I was looking for. If answer choice (B) weren’t true, and the likelihood of remembering a patient’s prediction is not affected by whether or not the change actually occurs, then the two rumors would be materially different, and what makes one of them illusory may not apply to the other. Since the logical opposite of answer choice (B) weakens the conclusion, this answer states a claim upon which the conclusion depends.
I hope that makes sense. It’s a tough question for sure, so I’m glad you asked for an explanation.