Logical Reasoning

PT21 · S3 · Q21 A number of seriously interested amateur astronomers

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A number of seriously interested amateur astronomers have tested the new Exodus refractor telescope.

Conclusion (given these findings)

Any serious amateur astronomer ought to chose the Exodus if she or he is buying a telescope for planetary observation.

Evidence

A bunch of serious amateur astronomers tested the Exodus, and, using it, they were able to observe planetary features in crisp detail, even though those features appeared only as fuzzy images in their 8-inch Newtonian telescopes.

Evaluate

Since this argument comes down to recommending This Option over Other Options, we need to consider the holistic set of pros and cons for each option.

If we switched from a Newtonian 8-inch to a 4-inch Exodus, would we serious amateur astronomers experience a Net Gain or Loss?

The argument tells us about one advantage of switching: - we can now observe some planetary features in crisp detail, rather than just as fuzzy images

Goal

To weaken this argument, we want to hear something negative about the Exodus (too pricey? too heavy? smells like rotten eggs?) or to hear something positive about Newtonian telescopes.

However, it does have to relate to serious amateur astronomers and to the idea of observing planets, since the conclusion is restricting its recommendation to those background conditions.

21.

Which one of the following most seriously weakens the argument?

  1. Telescopes of certain types will

    No Distinction, No Impact

    We're looking for something bad about the Exodus or good about the alternatives (Newtonian telescopes). This answer is talking about something that applies to all telescopes, so it's not going to give a specific edge to one telescope vs. another.

    12% picked this

  2. Correct

    Image quality is only one

    Why this is right

    This is a surprisingly weak correct answer, but it's the best available. The author makes an aggressive move from, "The Exodus was superior to the Newtonian telescopes when it comes to the image quality of planetary features" to the conclusion of "Okay, serious amateur who wants to observe planets should buy the Exodus". This answer is saying, "Hey, hey --- slow your roll. There's more to buying a telescope for planetary observation than just considering image quality. You need to also consider its weight, its price, its maneuverability, its ease of locating points in the sky, its ability to take Instagram-ready photos of what you're seeing through the eyepiece. This answer doesn't go as far as to say that Newtonian telescopes win when it comes to any of these other considerations, but simply pointing out that there are other considerations creates a cloud of doubt, where now it's possible that Newtonian telescope could win the head-to-head battle, if it's superior to the Exodus on other levels.

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

    73% picked this

  3. Many serious amateur astronomers have

    No Impact

    Whenever we have a conditional conclusion, we can't strengthen it by making the Trigger idea more likely nor can we weaken it by making the Trigger idea less likely. This conclusion was saying, "If you are buying a telescope for planetary observation, then you should go with the Exodus". If most amateurs aren't buying telescopes for that reason, that doesn't hurt the author's recommendation at all. It just means that the author's recommendation is only relevant to a smaller population of people. If I recommend Nature's Delight as the best vegan restaurant in town, you're not countering my recommendation at all by saying, "most people don't want to eat at a vegan restaurant". I never said they did. But for those who do, the best option is Nature's Delight.

    9% picked this

  4. The comparisons made by the

    Strengthens

    This makes the data set the argument is leaning on seem more robust. We might have objected, "Hey --- the Exodus isn't actually better at seeing crisp details. You just happened to look out on an atypically clear night." But this would fight that objection by saying that the amateurs compared the two telescopes on several different occasions, so potentially under a variety of viewing conditions.

    5% picked this

  5. The substance used to make

    Unclear Impact

    Does "different" mean better-different or worse-different or similar-but-different? The answer doesn't reveal whether this different substance is a positive or a negative aspect of the Exodus's lens.

    1% picked this

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