Logical ReasoningDifficulty: Easy

PT131 S1 Q19 Explanation

Geneticist: Genes, like viruses

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

TopicsSufficient Assumption

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Stimulus

Geneticist: Genes, like viruses, have a strong tendency to self-replicate; this has led some biologists to call genes "selfish." This term is, in this instance, intended to be defined behaviorally: it describes what genes do without ascribing intentions to them. But even given that genes are ascribed no intentions, the label "selfish" the best conditions for oneself; creating replicas of oneself is not selfish.

What this question is testing

Sufficient Assumption

Your task

Find the assumption that, if added, guarantees the conclusion follows.

Common trap

Answers that only partly bridge the gap, leaving the conclusion unproven.

Winning move

Identify the new term in the conclusion and pick the choice that links it to the evidence.

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

The question
19.

Which one of the following, if assumed, allows the geneticist's conclusion to

Answer choices

  1. Out of Scope1% picked this

    Bringing about the best conditions for oneself is less important than doing

    The importance of bringing about the best conditions for others is not relevant to the argument.

  2. Correct83% picked this

    Creating replicas of oneself does not help bring about the best

    Why this is right

    This provides the link between self-replicating and creating the best conditions for oneself.

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

  3. Out of Scope12% picked this

    The behavioral definition of "selfish" is incompatible with its

    The everyday definition of “selfish” does not play a role in the argument.

  4. Out of Scope2% picked this

    To ignore the fact that self-replication is not limited to genes is to

    Self-replication outside of genes does not play a role in the argument.

  5. Too Weak2% picked this

    Biologists have insufficient evidence about genetic behavior to determine whether it is best

    The argument goes further than suggesting that labeling genes as selfish is premature. The argument takes it a step further and advocates that genes are in fact not selfish.

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