Self-study
Spreading iron particles over the surface of the earth's oceans would lead to an increase in phytoplankton, decreasing the amount of carbon dioxide in the atmosphere and thereby counteracting the greenhouse effect. ███ █████ █████████████ ███ ██████████ ██████ ██ ██████████ ███ ████ ███████ ██ ██ ████████████ ████████ ████ ███ ██ ██ ████████ █████ ███ ██████ █████████ ████ ██ █████████ █████████ ████ ████████ ██ ███ ██████████ ██████ ██████ ███ ██ ███████████ ████████████
Summary
Despite the potential benefits, the author concludes that we should wait before spreading iron over the ocean to stop global warming. Why? The ocean is an important resource, and we don’t know what effects spreading iron might have.
Notable Assumptions
The author concludes that we should wait to implement a potential solution to global warming, but her only evidence is that we don’t yet know what the full effects on an important resource would be. The author is assuming that we shouldn’t alter these resources without knowing the full effects, so we’re looking for a conditional statement to explicitly state this rule:
If you don’t know what the effects would be, then you shouldn’t alter an important resource.
11.
The reasoning above most closely ████████ ██ █████ ███ ██ ███ █████████ ███████████
a
A problem-solving strategy ██████ ██ ███████████ ██ ███ ████ ███████ ██ ███ ████████ ███ ██████
If the sufficient and necessary conditions were swapped, this would prove our conclusion. As it stands, however, (A) only provides us with a necessary condition for a solution not being implemented.
b
Implementing a problem-solving ████████ ████ ██████ ██ █████████ ████████ ██ █████████████ ██ ███ ████████████ ███ ███ ██████████ ███████████
We know that the consequences of iron-seeding on the ocean are not known. (D) tells us that we should wait to implement iron-seeding based on this information, which proves the conclusion.
c
We should not █████████ █ ███████████████ ████████ ██ ███ ████████████ ██ █████ ██ ███ ████ ███████ ████ ███ ███████ ███████
Wrong trigger. We don’t know if the consequences of iron-seeing would be worse than global warming, only that we don’t know what those consequences would be.
d
We should not █████████ █ ███████████████ ████████ ██ ████ ████████ ████████ ████████ ██ █████████ █████████
Leads to the wrong conclusion. We don’t need to prove that iron-seeding should never be implemented, only that we should wait until we know the full effects.
e
As long as █████ ██ █ ███████████ ████ █ ████████ ███ ███████ █ ███████ ███ ███████ ██████████ ████ ████████ ████ █ ████████ ██████ ███ ██ ████████
Wrong trigger. We don’t know if iron-seeding might make global warming worse. We just don’t know what other side effects outside of global warming it might have.