PT49.S2.Q14 - scientist: a controversy in paleontology

Comments

• daniel.noah.pearlberg Free Trial Member

  July 2016 70 karma

  I haven't watched the video with J.Y.'s explanation, and I too read (D) as meaning that they were the first who did it- but I think that what's wrong with (D) is that "dexterity" is not the same as "free use of the hands". You can have dexterity without free use, and vice versa.
• legal_name Alum Member

  July 2016 edited July 2016 277 karma

  @daniel.noah.pearlberg I see where you're going with that and not trying to be difficult here, I swear, haha but isn't free use of hands necessary to develop dexterity? I might've overthought this question.
• daniel.noah.pearlberg Free Trial Member

  July 2016 70 karma

  Hmm, isn't it possible that the Uprighters and the Non-Uprighters had the exact same amount of dexterity, and the only difference between them (in terms of their hands) was that the Uprighters had free use of the hands and the Non-Uprighters did not?
  
• legal_name Alum Member

  July 2016 277 karma

  @daniel.noah.pearlberg I think you mean the opposite - that uprighters did not have free use of their hands and non-uprighters did? I guess my mistake is thinking that having dexterity implies you have free use of hands is a smaller assumption than the one in B. Or maybe it's just altogether incorrect.
• 1 Like

  daniel.noah.pearlberg Free Trial Member

  July 2016 70 karma

  (D) would be the correct answer if, instead of telling us about dexterity, it told us that the uprighters had no more free use of their hands than did the non-uprighters. In fact that would be a pretty good weakener, for the stimulus simply tells us that being upright makes free use of the hands possible- leaving open the possibility that there are plenty of other ways to get free use of the hands. And if being upright isn't necessary for free use of the hands, and the non-uprighters were able to get just as much free use of their hands, then the argument is stupid.
  But that's not what happens in (D). Instead, it tells us that the uprighters had no more dexterity than did the non-uprighters. Now, if having no more dexterity implies that they had no more free use of their hands, then (by the reasoning above) (D) would be correct. But having no more dexterity does NOT imply that they had no more free use of their hands. They could have the same level of dexterity, but different levels of "free use of their hands".
  So: (D) only weakens the argument if (i)[the uprighters having no more dexterity than the non-uprighters] implies that (ii) [the uprighters have no more free use of hands than the non-uprighters]. But (i) does not imply (ii), so (D) does not weaken the argument.
  
  Hope this helps, sorry for any lack of clarity, this question is definitely starting to make my head spin
  
• 1 Like

  BinghamtonDave Alum Member ⭐ 🍌🍌

  July 2016 8716 karma

  This is a pretty hard question. My particular difficulty was in the proposed relationship between "standing upright" and "free use of hands" in the stimulus. I was unsure of what "makes this possible" was supposed to signify: Something that is sufficient for "free use of hands"? Something that is sufficient for the relationship between: Advanced toolmaking---->free use of hands? Something that could be there but also doesn't have to be there, meaning that "Standing upright" didn't actively prevent "free use of hands"? All and all, what I took from this question is that the relationship is vague and doesn't exclude that there might be other things sufficient for "free use of hands." Because of that ambiguity, I didn't have a decent pre-phrase going into the answer choices (and even dreaded that they were going to test me on some sort of complex relationship I was unaware of!)
  
  Continuing on,notice that there is a small slide that we have all become accustomed to noticing within the stimulus. The contextual information focuses on the question of when prehistoric human ancestors "began to develop sophisticated tools" while the scientist's conditional relationship focuses on "advanced tool making." I think this is a prefect example of how the test writers can zero in on our biases when reading things. When I read the sentence "advanced tool making" I think of those assembly lines on that show "How It's Made" cranking out thousands of finely tuned torque wrenches calibrated up to the standards of the US department of Weights and Measures, not something that simply requires "free use of hands."
  
  The idea that the weakening answer was going to come in some iteration of the slide from "began to develop sophisticated tools" and "advanced toolmaking" is cast aside when the scientist states the conclusion: "I argue that they stood upright first." The support for this conclusion is the stated conditional relationship that we have to twist a tiny bit to read: "Develop sophisticated tools---->free use of hands." What this means is that "free use of hands" must be present if the development of sophisticated tools occur. That part we shouldn't quibble with. Instead, we should focus on is how the scientist makes this relationship relevant to the conclusion of "I argue that they stood upright first." The scientist does this by arguing that "standing upright" makes the necessary condition of the relationship "possible." Well, are there other things that also could make the necessary condition "possible"? Meaning, are there other things that don't actively prevent the necessary condition from occurring? How about not standing upright? Because if not standing upright makes it possible also, then what is so special about standing upright that the scientist had to based the conclusion on that "possibility"?
  
  We are asked to most weaken the argument.
  (A) isn't good. "Basic tools" doesn't do much for us.
  (B)Nice, but not perfect. Maybe they didn't develop the hunting weapons, but there are present.
  (C)This one I had the hardest time eliminating. Did "make possible" imply sufficiency? If it did, the n this would appear to me to be a negation of the relationship (anyone care to jump in, please do, still kinda unsure of this.) If something is sufficient for the necessary condition of a relationship containing a different sufficient condition is negated, does it destroy the line of reasoning?
  (D)I think there is 2 things wrong with this. First is the unneeded temporal dimension it adds to our reasoning. First began to stand upright? All we know from the reasoning in the scientist's argument is that standing upright came before developed sophisticated tools. We have no information on the time that elapsed between the two phenomena. Differentiating between time frames within the relationship given doesn't change the fact that the standing upright happened before the development of tools. The next part of the answer choice puts the standing upright crowd at minimum on par with the not standing upright crowd in the domain of dexterity-which again, plays to a nuisance that doesn't do much for us as far as weakening. The level of dexterity plays no role in the scientist's argument. What does instead is the "free use of hands." Both aspects of D seem to challenge the nuisances of particular aspects of the premises, rather than the relationship between the premises and conclusion. The test writers want us to equate these terms, they want us to not differentiate. An early upright and non-upright prehistoric human ancestor had comparable levels of hand dexterity, what we are concerned with is the free use of those hands afforded by the difference between those two. They can be just as equal dexterity-wise, but are they just as equal for "free use?" We have really no idea. We would do well to remember where hands were on the non-upright crowd. They would mostly be on the ground, away from "free use."
  (E)Doesn't talk about the makers of the tools.
• 1 Like

  BinghamtonDave Alum Member ⭐ 🍌🍌

  July 2016 8716 karma

  P.S. I don't love any of the answer choices. But B is the best.
• 1 Like

  legal_name Alum Member

  July 2016 277 karma

  @David3389
  @daniel.noah.pearlberg
  
  I really appreciate you guys taking the time to write out your explanations. I overthought this question completely. I just needed to see someone else break it down the way they saw it.
  Can't thank you both enough! Your responses were very helpful.