Logical Reasoning

PT110 · S3 · Q6 Standard archaeological techniques make

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Standard archaeological techniques make it possible to determine the age of anything containing vegetable matter, but only if the object is free of minerals containing carbon.

Conclusion (therefore)

It is not possible to determine the age of prehistoric paintings on limestone using standard archaeological techniques.

Evidence

Prehistoric paintings on limestone were painted with vegetable matter.

Standard techniques for determining the age of vegetable matter require that it is free of minerals containing carbon.

It is impossible to collect samples or prehistoric paint without removing limestone (which has carbon) with the paint.

Evaluate

Since the Anti-Conclusion is that , we need to think of a way around this roadblock.

We have to collect samples in order to analyze them for age, and any sample we collect will also contain limestone, which is a mineral containing carbon.

Standard techniques require that an object is free of minerals containing carbon.

Is there any way for this to work?

Maybe every sample will contain some limestone, but not spread the entire sample? In other words, maybe every 4 oz sample of paint will have 1 oz of limestone, but perhaps it's all located on one side of the sample and we can grab a "clean" oz or two of pure paint from the other side.

Maybe we can separate out the limestone from the paint? Is there a centrifuge that could send the limestone to one end and the vegetable matter to the other?

Goal

Look for an answer that helps us argue, .

6.

Which one of the following, if true, most seriously weakens the argument?

  1. There exist several different techniques

    Out of Scope: other techniques

    The conclusion we're fighting is specifically about whether "standard techniques" can do the job of dating this paint. If other techniques can collect samples of pigments without getting limestone, congratulation to them. But they don't pose any objection to the author, who is only talking about these techniques that can't avoid getting limestone in their paint samples.

    11% picked this

  2. Correct

    Laboratory procedures exist that can

    Why this is right

    The author thinks it's a dealbreaker that the paint samples will all contain limestone, because limestone contains carbon minerals, which screw up the standard dating techniques. But apparently it is possible to use the standard techniques, because we already have procedures by which we can just remove all the limestone from the sample. Problem solved!

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

    76% picked this

  3. The age of the limestone

    Out of Scope: age of limestone

    The conclusion only cares about whether we can determine the age of paintings, which means dating the paint pigment, which means dating the vegetable matter used to make the paint pigment. We don't care about what's possible in the world of determining the age of rocks like limestone.

    11% picked this

  4. Prehistoric artists did not use

    Strengthens

    Given that this sounds like it's just reiterating what a premise told us, "Prehistoric artists painted on limestone with pigments composed of vegetable matter", this should feel more like it's reinforcing the author's thinking than it is combating the author's thinking. If the prehistoric artists sometimes made paintings with something other than vegetable matter, then that would open the door to new possible ways in which we could use standard techniques to figure out the age of these paintings. So if they used lots of different substances, then there's more doubt about the author's argument, which only pertained to vegetable matter.. If they only used vegetable matter, then the author's argument is more sound.

    1% picked this

  5. The proportion of carbon to

    Strengthens, if anything

    This seems to rule out the sort of objection we were imagining in which a 5 oz sample of paint has 1 oz of limestone squeezed over to one side and 4 oz of paint filling the remainder. An uneven dispersion of carbon throughout the limestone could allow there to be lucky little pockets of "no carbon", from which we could grab out carbon-free paint sample. So if this answer is telling us that the carbon is evenly distributed throughout the whole sample, then it's harder to extricate the carbon we don't want from the vegetable matter we do. Thus, it would help the author.

    1% picked this

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