Logical Reasoning

PT148 · S3 · Q2 Archaeologist: For 2,000 years

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Archaeologist: For 2,000 years the ancient Sumerians depended on irrigation to sustain the agriculture that fed their civilization.

Conclusion (thus)

Modern civilizations that continue to rely heavily on irrigation for agriculture are likely to eventually collapse.

Evidence

The ancient Sumerians relied heavily on irrigation for agriculture and they eventually collapsed, once the irrigation had built up so many toxic salts in the soil that the soil was unable to support crops.

Evaluate

This argument relies on a Comparison, assuming that what happened with the Sumerian civilization is likely to happen to similar civilizations (those who use irrigation a lot).

When we're analyzing Comparisons, the author is usually assuming other similarities or assuming some crucial difference.

In this case, the author is Assuming Similarities between ancient Sumeria and these modern irrigating cultures.

She's assuming that the modern cultures will be doing irrigation long enough and intensively enough that they will eventually run into the same problem with toxic salts. (She's also assuming the local soil is similar enough that long-term irrigation could have similar toxic buildup effects).

And she's assuming that if/when that day of toxic buildup arrives, these modern civilizations don't have a Plan B to save their agriculture / save their civilization.

Goal

We're probably looking for an answer to provide a Meaningful Difference between these modern civilizations and that of the ancient Sumerians, a difference that would allow us to say that even though they are reliant on irrigation too, we shouldn't consider it likely that this irrigation will one day doom their civilization.

2.

Which one of the following, if true, most weakens the archaeologist's argument?

  1. Most modern civilizations could not

    No Impact

    This answer is only talking about whether or not most civilizations need to irrigate. For the ones that do irrigate, we're only concerned with that the possible civilization-ending repercussions there might be. This answer doesn't give us any information that helps us evaluate the soil / agriculture future of these modern civilizations who rely heavily on irrigation.

    1% picked this

  2. Factors unrelated to the use

    No Impact

    Sure, I mean something's gonna kill all of us. But if you're buddy Louie drowned while trying to swim the English channel, and you're saying to your other buddy, "Don't try to swim the English channel! You'll probably die like Louie did!", it's not a great objection for your friend to say, "ahhh, something would've killed Louie sooner or later." Given that bad soil due to irrigation was the death knell of the Sumerian civilization, it is useful to the author as evidence that other societies who rely similarly on irrigation may have the same fate. It makes no difference to that kind of argument to say, "If irrigation hadn't killed the Sumerians, something else would've."

    4% picked this

  3. Correct

    Many modern farmers use irrigation

    Why this is right

    This provides a meaningful difference where our author was Assuming a Similarity. Our author thinks that these modern civilizations who rely heavily on irrigation are going to have the same fate as the Sumerians, because over time these modern societies will also see that irrigation has built up toxic levels of salt in the soil, making it unable to support crops. This answer is saying, "No, the modern societies won't have to worry about that problem. They're different. They have better irrigation techniques that circumvent the salt problem that did in the Sumerians."

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

    80% picked this

  4. Many modern civilizations do not

    Out of Scope

    Out of Scope: ones that don't irrigate We're all really happy for these other civilizations, but they are irrelevant to the conversation this author is having. Her conclusion is only about civilizations that do irrigate (heavily, at that).

    7% picked this

  5. The soil of ancient Sumeria

    Too Weak

    "Some" means at least one, so in this chemical residue sense, if we say "this soil contains some gold", we could mean "at least one molecule of gold". Saying that the Sumerian soil already had "at least some molecules of toxic salts before they started irrigating" doesn't clear irrigation's name of the charges of "killing Sumerian civilization". The evidence is what it is. Whatever the levels of toxic salt were prior to irrigation, the soil was still able to support crops (2000 years worth of agriculture that fed the Sumerian civilization). It was the increase to toxic levels of salts (caused by irrigation) that made the soil unable to support crops. So this answer cannot excuse irrigation of being the cause of the Sumerian collapse.

    8% picked this

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