Logical ReasoningDifficulty: Hard

PT138 S2 Q15 Explanation

Psychologists recently conducted

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsNecessary Assumption

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Stimulus

Psychologists recently conducted a study in which people from widely disparate cultures were asked to examine five photographs. Each photograph depicted the face of a person expressing one of five basic human emotions—fear, happiness, disgust, anger, and sadness. The people in the study were asked to identify the emotion being expressed in are genetically predisposed to associate certain facial expressions with certain basic emotions.

What this question is testing

Necessary Assumption

Your task

Find the assumption the argument requires in order for its conclusion to hold.

Common trap

Answers that would help the argument but aren't strictly required (sufficient, not necessary).

Winning move

Negate each choice — the right one breaks the argument when negated.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
15.

Which one of the following is an assumption on which the

Answer choices

  1. Out of Scope11% picked this

    For each photograph, the emotion that the subjects agreed was being expressed was the emotion that the person

    The emotion felt by the person being photographed is not relevant since the person observing the photograph could only ascertain the emotion being expressed. This answer has more to do with whether the emotion being expressed was genuine, which is not relevant to the argument.

  2. Too Strong17% picked this

    One's emotional disposition is not influenced by

    This would include the expression of other emotions beyond the five basic ones included in the study.

  3. Weakens2% picked this

    Some behaviors that are present in people from widely disparate cultures are

    This weakens the argument by providing an alternative explanation to the one reached in the argument.

  4. Correct65% picked this

    If there is a behavior common to people of widely disparate cultures, then there is probably a genetic

    Why this is right

    This links the evidence WDC + SE ? GP to the conclusion with an “if/then” relationship.

    Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

  5. Too Strong5% picked this

    The people whose faces were depicted in the photographs were not all from

    Even if the people depicted in the photographs were all from the same culture, the fact remains that for each emotion it was recognized by people from widely disparate cultures in the same way.

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