Self-study
Astronomer: Astronomical observatories in many areas have become useless because light from nearby cities obscures the stars. ████ ██████ █████ ████ █████ ████████████ ███ ██████ ███ ███████ ████ ████████████ ████ ██████ ██ ███████████ ████ ██ ███████████ ████████ ███ █████ █████████████ ████ ███████ ██████████ ██████ █████ ███ ████ ███ ██████████ ███████████ ████████ ███ █████████ ███████ ██████ █████ ████ ██████ ███ █████ █████ █████████ ██ ██ █████████ ████████ ██ ████ ████ ████████████ ███████ ███ ██████████ ████ ██████
Summarize Argument: Counter-Position
The astronomer introduces a problem: many astronomical observatories are no longer useful because light from cities nearby interferes with the view of the stars. Some people say that this problem of light interference is inevitable, because streetlights are necessary for safety.
But the astronomer disagrees. She points to Sandsville, where restrictions on unnecessary lighting and the installation of special downward-directed streetlights have allowed the city both to have streetlights and to keep the view clear for the local observatory. From this example, the astronomer concludes that it is possible to have both well-lighted streets and keep the skies clear for observatories. The problem of light interference isn't inevitable.
Describe Method of Reasoning
The astronomer counters a position held by others: the idea that it is "inevitable" to have light pollution from cities interfere with observatories, since streetlights are necessary for safety. She responds to this position with a counterexample, pointing to Sandsville, which keeps its skies relatively dark by restricting unnecessary lighting and using special street lamps. This example disproves the claim that city lights will inevitably interfere with the view for observatories.
11.
The astronomer's argument proceeds by
a
appealing to a ██████████ █████████ ██ █████████ █ ██████ ████ ██████
The astronomer does not appeal to a scientific authority anywhere in her argument. We also don't know how many people actually hold the belief the astronomer is arguing against. The stimulus says "many people", which is too vague to tell us the belief is actually "widely held."
b
questioning the accuracy ██ ████████ █████ ██ ███████ ██ ███ ████████ ████████
This might be tempting, because it's easy to assume that the people who think city lights will inevitably interfere with observatories just don't know about Sandsville. But it's important to see that the argument doesn't mention any evidence given in support of the opposing position, let alone question its accuracy. We don't know what kinds of evidence these people are relying on. Maybe they didn't feel the need to mention any — it's hard to argue with the general claim that streetlights are needed for safety. So even if we can infer that these people probably don't know about Sandsville, the point of the astronomer's response is not to say that their evidence is inaccurate. It's to point to Sandsville as a counterexample that disproves these people's main point.
c
proposing an alternative ██████████ ███████████ ███ █ ███████ ██████████
The astronomer does not propose an alternative explanation for light interference or any other "natural phenomenon."
d
making a distinction ███████ █████
The astronomer does not distinguish any terms. She provides a counterexample that disproves an opposing claim.
e
offering a counterexample ██ █ ███████ █████
This is correct. The general claim is the other people’s argument that interference from city lights with observatories is inevitable, since cities need streetlights for safety. The counterexample the astronomer offers is the city of Sandsville, which does not experience light interference with its observatory despite having streetlights.