Vithal wrote:
It is illogical to infer a second and different effect from a cause which is known only by one particular effect. This is incorrect because the inferred effect must necessarily be produced by some different characteristic of the cause than is the observed effect, which already serves entirely to describe the cause.
Which one of the following arguments makes the same logical error as the one described by the author in the passage?
(A) An anonymous donor gave a thousand dollars to our historical society. I would guess that that individual also volunteers at the children’s hospital.
(B) The radioactive material caused a genetic mutation, which, in turn, caused the birth defect. Therefore, the radioactive material caused the birth defect.
(C) The tiny, unseen atom is the source of immense power. It must be its highly complex structure that produces this power.
(D) The city orchestra received more funds from the local government this year than ever before. Clearly this administration is more civic-minded than previous ones.
(E) If I heat water, which is a liquid, it evaporates. If I heat hundreds of other liquids like water, they evaporate. Therefore, if I heat any liquid like water, it will evaporate.
My take on this question is a bit different. Here goes.
The statement describes that there's a one to one correspondence between cause and effect; one effect can be caused by one cause only. Thus this holds good:
cause --> effect 1
but not this:
|----> effect 1
cause --|
|----> effect 2
Now coming to options:
(A) Talks about two effects - "donation of 1000 dollars" and "volunteering at the children's hospital". No cause is discussed. We can safely ignore it.
(B) One cause "radioactivity" had the effect "genetic mutation". Then one cause "genetic mutation" had the effect "birth defect". So far so good - in line with the flawed reasoning provided in the basic statement. However, now it says "genetic mutation" caused "birth defect". This "chained cause-effect relationship" is not described in the statement, so doesn't fit well.
(C) Cause -> effect is "complex structure" -> immense power. Its right as far as the statement goes, but it has not made any flawed logical conclusions - so we can let it go too.
(D) Same single cause-effect relationship described. Nowhere it describes the assertion that one cause should have one effect or vice versa. This also doesn't fit well.
(E) "Heating" (cause) leads to "evaporation" (effect). Then comes the assertion that thus, heating causes evaporation (only one effect - evaporation - attributed to one cause - heating). Of course this is flawed, because there's another effect - water/liquid getting hot. This is a flawed reasoning.
Thus I'd go with E.
Those who think the option would have been B, might be correct in reasoning that the single cause "radioactivity" is attributed to the effect "birth defect" (while in reality the birth defect may be caused by anything else as well - say chemicals). This is true. However the assertion uses a "cause chaining" in which the cause's (genetic mutation's) cause (radioactivity) is attributed to the effect (birth defect). This is not clearly described in the statement.
Anyone with a different reasoning?
Can you please post the OA Vithal?