Logical Reasoning

PT13 · S4 · Q17 Recent research shows that hesitation

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Recent research shows that hesitation, shifting posture, and failure to maintain eye contact are not reliable indicators in discriminating between those who are lying and those who are telling the truth.

Conclusion (the research indicates)

The behavioral clues mentioned, such as pupil dilation and small facial muscle movements, are considered better indicators for detecting lies than hesitation and posture shifting.

Evidence

Recent research reveals that hesitation, shifting posture, and failure to maintain eye contact are unreliable for distinguishing between liars and truth-tellers.

Evaluate

Since we're talking about which method is better for lie detection, we could put this into Plan / Goal format:

GOAL: to be able to figure out whether someone is lying PLAN: check to see whether their pupils dilate or their facial muscles make small movements.

Since the question stem wants us to impugn this method, we'd be thinking,

Goal

Let's identify an answer that provides a compelling reason why these "better" clues might not be as reliable for lie detection.

17.

Which one of the following provides the strongest reason for exercising caution when relying on the “better” clues mentioned above in order to discover whether someone is lying?

A person who is lying
No Impact
While awareness of being observed might influence behavior, the argument centers on "uncontrollable" behavior like pupil dilation, which should ideally not be influenced by awareness. Therefore, this doesn't provide a strong reason against these clues' reliability.
7% picked this
Someone who is telling the
No Impact
This answer has nothing to do with whether the plan of checking pupils / facial muscles would help us assess whether someone is presently lying.
0% picked this
A practiced liar might have
No Impact
This choice doesn't address the reliability of the uncontrollable indicators. Control over posture and eye contact relate to the dismissed unreliable clues, not the "better" ones.
14% picked this
Correct
A person telling the truth
Why this is right
If someone telling the truth becomes emotionally affected by suspicion or the situation, they might exhibit similar physiological responses—like pupil dilation and facial muscle movements—as a liar. There was a Breadcrumb telling us that pupil dilation is caused by emotional arousal, and this answer is saying that the truth-tellers might also get emotionally aroused. So if we see dilated pupils, we won't know whether they were caused by the emotional arousal of "being stressed about your lies" or the emotional arousal of "being wrongly suspected as a liar".
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
74% picked this
Someone who is lying might
No Impact
This seems to suggest that in some cases both method 1 and method 2 would be eligible, but it doesn't give us any way to argue that one method is better / worse than the other.
4% picked this

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