to the top

#5 - Brain-scanning technology provides information about

LSAT Novice
Posts: 1
Joined: Mon Jul 31, 2017 7:49 pm
Points: 1

Hi, for this question I understand the concept behind answer choice E and how it can be correct but the words "only if" threw me off. This seemed to narrow to me and an assumption. Could you please explain to me how this is correct although it says only if?
Jonathan Evans
PowerScore Staff
PowerScore Staff
Posts: 681
Joined: Thu Jun 09, 2016 2:12 pm
Points: 570
Location: DFW, Texas

Hi, West1001,

Great question. The issue here has to do with how necessary the reliability of people's reports of their thoughts are. Let's revisit the language of the stimulus:

[r]esearchers must be able to rely on the accuracy...

The "must be" is key. "Must" introduces a necessary condition for the success of researchers' efforts, diagrammed thus:

    Info helps researchers :arrow: Researchers able to rely on accuracy of reports

In the credited response, "only if" introduces the same necessary condition using different language. These paraphrases are a hallmark of Main Point questions. Consider reviewing sufficient and necessary condition indicator words (Logical Reasoning Bible Chapter 6, page 172, 2017 edition). Otherwise, excellent work and please follow up with further questions.