Logical ReasoningDifficulty: Hard

PT105 S1 Q21 Explanation

Two doctrines have been greatly

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

TopicsNecessary Assumption

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Stimulus

Two doctrines have been greatly influential in this century. The first holds that the explanation of any historical event must appeal to economic factors. The second attempts to account psychologically for all historical events, especially in terms of early childhood experience. Both doctrines, however, are mistaken. Certainly there have been events that the early childhood experiences of the major participants in the event.

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
21.

The argument depends on assuming which one of

Answer choices

  1. Correct46% picked this

    The first doctrine precludes any noneconomic factors in explanations of

    Why this is right

    We could have written a similarly correct answer about the second doctrine, that it "precludes any non-psychological factors in explanations of historical events". It's just getting at the idea that this author was assuming the doctrines were mutually exclusive. If we negated this answer, it would be saying this objection: "Yo, author --- the first doctrine allows for noneconomic factors to also be factors in explanations of historical events. It's saying you must always appeal to economic factors, but it's not saying you can only appeal to economic factors. Hence the fact that there are events that were due to economic and psychological stuff doesn't do anything to weaken the validity of this doctrine."

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

  2. Too Strong: only6% picked this

    The second doctrine places importance only on

    The text tells us that the second doctrine attempts to account psychologically for all events, especially in terms of early childhood experience. But if I say that "Harvard cares especially about your LSAT score", that doesn't mean "Harvard's admission committee places important only on your LSAT score".

  3. Too Strong: perfectly equal16% picked this

    Historical events are influenced as much or as little by economic factors as

    The author doesn't have to assume that the influence of economic / psychological factors is perfectly in balance, as this answer choice is saying. He's only saying that some events are influenced by both, not that the sum total of historical events are influenced equivalently by both.

  4. Out of Scope13% picked this

    One is likely to find that both economic and psychological explanations have been proposed for

    Out of Scope: have been proposed Too Strong: any The argument was talking about two influential doctrines, what they hold or what they've attempted to do in relation to explaining historical events. This answer is saying that for every single historical event every, you're likely to find both an economic and a psychological explanation that's already been proposed. That's an extreme idea that suggests that both doctrines have already attempted to explain most historical events. There are a lot of historical events in history. We have no reason to believe the author thinks that both of these schools of thought have already proposed explanations for the majority of them. In fact, the author's argument rests on the idea of certain events that were due to both economic and psychological factors, and she doesn't even need to assume for those events that economic and psychological explanations have been proposed. The notion of whether proposed explanations already exist is not in this conversation. The author is only speaking to the appropriateness of there being an explanation of this type or that type (not whether it's already been proposed).

  5. Too Strong: needed / any19% picked this

    Appeals to both economic and psychological factors are needed to understand any

    The author hasn't committed to the very extreme notion that a proper understanding of every single historical event ever requires both economic and psychological dimensions to it. She is only saying that "there have been (at least some) events whose proper understanding would require acknowledgment of both economic and psychological factors".

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