Logical Reasoning

PT113 · S4 · Q25 In ancient Mesopotamia, prior to 2900 B.C

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In ancient Mesopotamia, prior to 2900 B.C., wheat was cultivated in considerable quantities, but after 2900 B.C. production of that grain began to decline as the production of barley increased sharply.

Curious Fact

Why was there a decline in wheat production around 2900 B.C. (as barley increased sharply)?

Author's Explanation

Because of too much irrigation and not enough drainage, there was an accumulation of salt in the soil (and the salt was bad for the wheat, presumably).

Evaluate / Goal

We can Strengthen an author's explanation / hypothesis two ways:

rule out an Alternate Explanation for the curious fact, or increase the plausibility of the Author's Explanation

25.

Which one of the following, if true, most helps to support the historians' contention concerning the reasons for the decline in wheat production in ancient Mesopotamia?

  1. The cultivation of barley requires

    No Impact

    If the author had thought that lack of water contributed to the decline of wheat, then this would strengthen the plausibility of why wheat would decline while barley would rise. But the author thought excessive irrigation (an abundance of water) is what led to wheat's decline.

    10% picked this

  2. Correct

    Barley has much greater resistance

    Why this is right

    The most common type of plausibility-strengthener is an answer that sort of gives you a "No Cause, No Effect" data point. The author thought that excessive salt in the soil killed off wheat. If she were right, then shouldn't excessive salt in the local soil have also killed off barley? According to this answer, no. Barley can tolerate a lot of salt. So if the author thinks "sensitivity to salt in the soil caused the decline of wheat", then it adds some plausibility to have a data point that looks like "this other contemporaneous thing, barely, that didn't have sensitivity to salt, didn't decline (it increased sharply)."

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

    76% picked this

  3. Prior to 2900 B.C., barley

    No Impact

    This seems to just be telling us that barley has been around for a while, though not as popular as it became after 2900 B.C. But it doesn't give us any clues as to why that switch occurred (decline wheat, uptick in barley), and the why is what we're investigating.

    2% picked this

  4. Around 2900 B.C., a series

    Weakens

    This offers an Alternate Explanation for the decline of wheat, so it would weaken the need for the Author's Explanation.

    8% picked this

  5. Literary and archaeological evidence indicates

    Weakens, if anything

    This is either like (C), in that it's just telling us what we already know ... "Prior to 2900, wheat was the star. After 2900, barely got big." Or it's like (D), in that it's giving us an alternate explanation for why wheat declined and barley surged: it wasn't that salty soil killed off wheat; people just wanted lots of barley in their diet.

    5% picked this

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