Politician: All nations that place a high tax on income produce thereb

OFFICIAL EXPLANATION

This problem is a complete conditional argument containing conditional premises and a conditional conclusion. Here is a breakdown of the argument: HT = nations that place a high tax on income, NI = negative incentive for technological innovation, FB = fall behind in the international arms race; also, wind up in a strategically disadvantageous position, LV = lose voice in world affairs. The first sentence contains two sufficient condition indicators (the word “all”) and can be diagrammed as a chain: HT
NI
FB. The next sentence paraphrases “fall behind in the international arms race” as “wind up in a strategically disadvantageous position” and can be diagrammed as: FB
LV. Because the two statements have FB in common, a single long chain can be created: HT
NI
FB
LV. From our discussion of conditional reasoning we know that a chain of this length contains many inferences. The conclusion, when paraphrased, tries to make a contrapositive: The phrase “nation wants maintain its value system and way of life” is a very rough equivalent of “wind up in a strategically disadvantageous position” and “lose a voice in world affairs.” The paraphrase is not a perfect equivalent because the conclusion discuses values, and the premises do not. For our purposes, we will symbolize this condition as: ~FB and ~LV. The phrase “must not allow its highest tax bracket to exceed 30 percent of income” is the equivalent
of HT. Thus, the diagram for the conclusion is: ~FB and ~LV~HT30. Thus, based on the chain of reasoning provided, we have a reasonable conclusion, but not a perfect one because the paraphrase was not exact. The question stem is a Weaken, which means that four of the answers will weaken the argument and the one correct answer will either have no effect on the argument or will strengthen the argument.

Answer choice (A): This answer attacks the necessary condition of the conclusion by showing that taxes could exceed 30% before problems occurred.

Answer choice (B): This answer attacks the first half of the first sentence, which states that high taxes necessarily produce a negative incentive for technological innovation. Because taxes lower an individual’s income, the higher the tax, the greater the relative restriction on making money. Answer choice (B) shows that higher taxes would not necessarily produce low innovation because innovators do not care about the amount they earn.

Answer choice (C): This answer attacks the part of the argument that equates “fall behind in the international arms race” as “wind up in a strategically disadvantageous position.” If the two are not equated, then the chain of premises breaks down.

Answer choice (D): Like (C), this attacks a portion of the argument where the author equates terms. In this case, the paraphrase in the conclusion was not exact, and this answer exploits that gap.

Answer choice (E): This is the correct answer. The answer does not hurt the argument because the stimulus specifically states that “Those nations that, through historical accident or the foolishness of their political leadership, wind up in a strategically disadvantageous position...” So, the actual reason the nation ends up in a disadvantageous position is not critical. It could be either foolishness or historical accident. So, an answer that asserts that it is foolishness and not historical accident has no effect on the argument.