Logical Reasoning

PT127 · S2 · Q23 Ecologist: Without the intervention

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Ecologist: Without the intervention of conservationists, squirrel monkeys will become extinct.

Given

Without the intervention of ~I → E conservationists, squirrel monkeys will become extinct.

But they will survive [not go FP → ~E extinct] if large tracts of second-growth forest habitat are preserved for them.

Squirrel monkeys flourish in PSIF >> F second-growth forest because of the plentiful supply of their favorite insects and fruit.

Evaluate

The only common term are the logical opposites of "surviving vs. going extinct". If we realize we can represent that with the same term, ~E vs. E, then we'll see that the two conditionals chain together to give us this:

~I → E → ~FP FP → ~E → I

The last claim is causal, and "flourishing" is more than just not-going-extinct. It's a particular type of surviving, so we don't want to equate with "survive vs. go extinct". So we'll just leave that last claim alone.

The correct answer will probably reward us for recognizing the conditional chain.

23.

Which one of the following can be properly inferred from the ecologist's statements?

  1. No habitat other than second-growth

    Reversal

    This reverses an implication of PSIF → SGF the third statement.

    2% picked this

  2. At least some of the

    Too Strong

    The statements do not ensure that conservationists will indeed intervene to help the squirrel monkeys.

    22% picked this

  3. Without plentiful supplies of their

    Negation

    This relies on negating the ~PSIF → ~FP second statement. ~FP → E ∴ PSIF → E To say that if the forest is not ~FP → E preserved, then the squirrel monkeys will become extinct negates the second statement.

    9% picked this

  4. If conservationists intervene to help

    Negation

    This negates the first statement. I → ~E

    9% picked this

  5. Correct

    Without the intervention of conservationists,

    Why this is right

    This combines the first and ~I → E second statements. E → ~FP ∴ ~I → ~FP

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

    58% picked this

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