I have a doubt.
A proposed change to federal income tax laws would eliminate deductions from taxable income for donations a taxpayer has made to charitable and educational institutions. If this change were adopted, wealthy individuals would no longer be permitted such deductions. Therefore, many charitable and institutions would have to reduce services, and some would have to close their doors.
The argument above assumes which of the following?
(A) Without incentives offered by federal income tax laws, at least some wealthy individuals would not donate as much money to charitable and educational institutions as they otherwise would have.
(B) Money contributed by individuals who make their donations because of provisions in the federal tax laws provides the only source of funding for many charitable and educational institutions.
(C) The primary reason for not adopting the proposed change in the federal income tax laws cited above is to protect wealthy individuals from having to pay higher taxes.
(D) Wealthy individuals who donate money to charitable and educational institutions are the only individuals who donate money to such institutions.
(E) Income tax laws should be changed to make donations to charitable and educational institutions the only permissible deductions from taxable income.
My question is whether choice D
"Wealthy individuals who donate money to charitable and educational institutions are the only individuals who donate money to such institutions."
can be called a stengthener
According to the definition of strengthener any new statement that makes the conclusion more believable is a strengthener.
Yes, option D can be called a strengthener because as you correctly said, it makes the conclusion more believable.
Now, this choice does make the conclusion more believable, but with an assumption that these wealthy individuals will contribute less if they don't get the tax incentive. Without this assumption, can choice D make the conclusion more believable by itself?
Without this assumption, option D will not be able to strengthen the conclusion because if the wealthy individuals are going to donate the same amount of money even when there are no tax incentives, then the conclusion just cannot hold, no matter how many strengtheners you provide.
So my doubt is that if a statement makes a conclusion more believable, but with the help of another statement which is not explicitly stated in the passage, can it be called a Strengthener?
Same for weakener ie if a statement makes a conclusion less believable ,but with the help of another statement which is not explicitly stated in the passage, can it be called a Weakener?
The answer to both the above questions is YES. When we say that a strengthener increases the belief in the conclusion and not necessarily prove the conclusion, we mean that the conclusion can still not hold true even in the presence of a strengthener. Right? Because it only increases belief and does not necessarily prove the conclusion correct.
So, if the conclusion does not hold in a situation (which will be the case when the assumption does not hold), then obviously it's futile to even say that the strengthener has increased the belief in the conclusion. It cannot do so simply because the conclusion does not hold.
So, all in all, you generally require assumptions for strengthener to strengthen the conclusion. Similar observation holds for weakeners also.
Now, here is the main thing: you cannot assume anything and everything even counter-intuitive things which go against the common sense. You have to make logical common sense assumptions when evaluating option statements for strengtheners or weakener.
For example, in the question above, the passage is essentially saying that one benefit of donation (i.e. tax deductions) is no longer there. Now, when one benefit is removed for any product or service, it is only logical to assume that people who valued that benefit will reduce their consumption of the product or service. In this case, similarly, it is only logical to think that some wealthy who valued the benefit of tax deduction will reduce their donations. So, we are making a very logical assumption, not a far fetched one.
I think this is an important thing to understand: you can make assumptions but they should not be counter-intuitive or far fetched. For example: you cannot assume in this question that by removing one benefit of tax-deduction, no wealthy individual will donate at all. This is a far-fetched one.
So, just be careful while making assumption when evaluating option statement for weakeners and strengtheners.
Hope this helps
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