Self-study
Spokesperson: Contrary to what some have claimed, Conclusion our group's "Clean City" campaign has been a rousing success. █████ ████ ███ ██████ ██ █████ ██ ███ ██████ ███████ █████ ██ █████████████ █████ ████ ████ ███ ████████ ██████
Summary
The author concludes that our group’s “Clean City” campaign has been successful.
Why?
Because the amount of trash on the city’s streets today is a lot lower than when the campaign began.
Notable Assumptions
The author assumes that one of the goals of the campaign was to reduce the amount of trash on the city’s streets.
The author assumes that the campaign caused the reduction in trash on the city’s streets.
2.
Which one of the following ██ ██ ██████████ ████████ ██ ███ ██████████████ █████████
a
The amount of █████ ██ ███ ██████ ███████ ███ ███ █████████ ██ ███ ████ ████ ██ ██████ ██████ ███ ████████ █████ ████ ██ ███ ██████ ███ █████████
Necessary, because if it were not true — if the amount of trash on the city’s streets WAS declining at the same rate or faster before the campaign began than it did during the campaign — then we have no reason to think the campaign caused the reduction in trash. The reduction could have simply been a continuation of whatever causal forces were already in place prior to the campaign.
b
Those who claim ████ ███ ████████ ███ ███ ████ █ ███████ ███████ ███ ███████ ██ ███ ██████ ██ ███ ███████ ██ ███ ██████ ██ █████ █████ ███ ████████ ██████
Not necessary, because the reasoning isn’t based on the people who believe that the campaign was not a success. Those people are mentioned purely as context — but they play no role in the reasons given for the conclusion.
c
The campaign has ████ ████ ██████████ ██ ████████ ███ ██████ ██ █████ ██ ███ ██████ ███████ ████ ███ ███ █████ ████████ ██ ███ █████
Not necessary, because the argument does not compare the “clean City” campaign to any other campaign.
d
The spokesperson's group ███ ███ ███████ ███ ███████ ███████ ██ ███████ ███ ████████ ██ █████████ ██ ███ █████████
Not necessary, because whether the author of the argument has received funding to say what she says has no bearing on the logic of her argument.
e
The amount of █████ ██ ███ ██████ ███████ ███ ████████ ████████ ██████████ ███ ██████ ██ ███ █████████
Not necessary, because whether the trash declined steadily or decline ins some other pattern (like a sudden drop) is irrelevant. The campaign can still have a causal impact on reduction of trash without that reduction occurring at a steady rate over the course of the campaign. Maybe, for example, it takes time for the effect of a campaign to build, and the effects occur all at once toward the end of the campaign.