George: Some scientists say that global warming will occur because people are releasing large amounts of carbon dioxide into the atmosphere by burning trees and fossil fuels. We can see, though, that the predicted warming is occurring already. In the middle of last winter, we had a month of springlike weather in our area, and this fall, because of unusually mild temperatures, the leaves on our town’s trees were three weeks late in turning color.
Which one of the following would it be most relevant to investigate in evaluating the conclusion of George’s argument?
Conc: Global warming is already occurring
Prem: Weather in my area is weirdly warm
Pre-thinking - This is a sampling flaw. Can we assume that the weather in George's area is a representative sample of global weather patterns?
To analyze that argument core, we are asking ourselves, "If I accept that the weather in George's area is weirdly warm, do I have to accept that global warming is already occurring?"
(A) whether carbon dioxide is the only cause of global warming -- Incorrect --He never claimed to know what is causing global warming. He only claimed that global warming is happening.
(B) when leaves on the trees in the town usually change color -- We believe George's premise, that the leaves were late in changing color. We don't need to question this.
(C) what proportion of global emissions of carbon dioxide is due to the burning of trees by humans --We don't care exactly what proportion of CO2 emissions comes from burning trees. George's argument core has nothing to do with CO2 emissions or trees. That 1st sentence has nothing to do with George's argument core.
(D) whether air pollution is causing some trees in the are to lose their leaves --This is temptingly close to an answer that would propose an alternative cause for why the leaves in George's area are late in turning color. However, this isn't about causing leaves to turn color more quickly or slowly. It's about leaves falling off. That's not relevant to George's evidence or his conclusion.
(E) whether unusually warm weather is occurring elsewhere on the globe more frequently than before - Correct - If we say unusually warm weather IS happening globally more frequently than before, then we strengthen George's argument that global warming is currently happening.
If we say unusually warm weather IS NOT happening globally more frequently than before, then we weaken George's argument that global warming is currently happening.
Answer E
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