QUESTION TEXT: Astronomer: This country's space agency is currently …
QUESTION TYPE: Principle – Justify
CONCLUSION: We should not cancel the space telescope project, even though it is over budget.
REASONING: If we cancel now, we will have wasted all the money that we have spent. We have spent more so far than would be required to complete the project. (e.g. They have spent $2 billion and only need to spend $1 billion more)
ANALYSIS: Principle – Justify questions are straightforward. We just have to say “if the evidence is true, then we should do the conclusion”. i.e. a moral statement that we “should” do something. So, if an argument says “Let’s go to Chicago, because the city starts with C!”, then the answer will say “You should go to a city if its name starts with C”.
It’s that simple. And note that the conclusion will always be in the necessary condition. E.g. “Starts with C —> Should go”.
Here, the conclusion is “do not cancel/should complete”. You could answer this question just by skimming the answers to look for that. Only the correct answer has the conclusion as the necessary condition!
The sufficient condition will be the evidence from the argument. In this case, something like: “we spent a lot —> should not cancel/should complete”.
___________
- This is in the form of “Should not cancel —> X”. We need an answer in the form of “X —> should not cancel”. The conclusion must be in the necessary condition. Things that come before the word“unless” are sufficient.
Also, this should have been more specific about money, making clear that we’ve spent more money than will be required to complete the project. - CORRECT. This matches. We have already spent more than half the money, because we’ve spent more than will be required to finish the project. According to this answer, that means we should complete the project.
This is the only answer that has “complete the project” in the necessary condition.
Diagram: Spent more than half the total cost —> should complete the project - This contradicts the astronomer! They’re telling us not to cancel the project.
- This contradicts the astronomer! They’re telling us we should commit more money and finish the project.
- This tells us nothing, because the astronomer doesn’t mention whether the new telescope will help lead to important new discoveries.
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MemberStratos says
I politely disagree with your reasoning why answer choice A is wrong. Here is mine (please correct me if my explanation has flaws):
The AC says “should not cancel unless xy”, means that “if we cancel, then xy must happen”.
The AC says: cancel –> money spent small relative to overall-budget –> not over-budget. Drawing the contra-positive would be over-budget –> don’t cancel. So, at a first glance, it is very tempting to choose it, as, according to the first sentence, we are over-budget, therefore the sufficient condition of the principle in answer-choice A is given.
The astronomer, though, says: [money already spent > additional money required] + [money spent would be wasted] –> don’t cancel.
Therefore, the reason why (A) is wrong in my opinion is that the principle would not justify the astronomer’s argument! The fact that the new space telescope is over-budget is only mentioned in the context, it is NOT used by the astronomer as a premise for his conclusion.
If we take the contrapositive of what is stated in (A), it would be: over-budget –> don’t cancel. If valid, it would only justify the conclusion, NOT the astronomer’s argument (which is more than its conclusion, means it also consists of the premise that supports it)!
It’s like I’m saying “Pork has a lot of fat. Mohammad eats pork every day. But, in my opinion, he should not continue doing that, as it is not in accordance with his religion.”
Does the principle: “A person should not eat pork unless it contains little to no fat” justify my argument?
FounderGraeme Blake says
You’re correct, I drew A wrong. I guess unless statements can get all of us sometimes. And you’re correct, the principle simply doesn’t apply.
Note: This is an old comment but I wanted to address the correction.