It is the central tenet of the ethical theory of the German Idealist

Question

It is the central tenet of the ethical theory of the German Idealist thinker Immanuel Kant that a person must not be treated as a means to an end but as an end only unique unto herself or himself. Therefore, it is wrong to use animals for food or clothing, for in doing so, we reduce them to mere instrumentalities and fail to consider their uniqueness.

Which of the following, if true, is the best criticism of the speaker's use of Kant's ethical doctrine?

A) Kant never considered the possibility that animals might be deserving of ethical treatment 
B) The use of animals for food and clothing is offensive to many people who themselves consider animals ends and not means 
C) Kant implies that rehabilitation is not a legitimate objective of the penal system because it treats the criminal as an end 
D) In nature, every animal is a potential source of nourishment for other animals below it on the food chain 
E) Kant's conclusion about treating humans as ends rests upon the assumption that humans have the ability for rational thought

Source: CR Archive

DavidTutorexamPAL · Answer

The answer is E.

We can find the answer using the  Logical  approach, since this question is about figuring out the premises for the argument given. 
The argument takes a claim Kant made about humans and extrapolates it to animals. Therefore, since our goal is to weaken the claim, we will look for a fundamental difference between humans and animals that makes this extrapolation illegitimate.  This is exactly what (E) gives us: Kant's conclusion about treating humans as ends rests upon the assumption that humans have the ability for rational thought
  - if this is the criteria upon which Kant's claim rests, it does not apply to animals (which are not capable of rational thought).

GittinGud · Answer

How do we know for sure that animals are not capable of rational thought.

abhishek31 · Answer

Hi, can someone please elaborate on the explanation? just didnt get the whole statement in the first place.

kartickdey · Answer

it is not right that animals do not have the rational thought.

Pratyaksh1907 · Answer

After reading the argument, we can come to a deduction that how can the author derive the conclusion about animals on the basis of Humans, right?

kartickdey

it is not right that animals do not have the rational thought.

So, if you read choice E, it is directly differentiates animals Vs humans on the basis of rational thinking. If we think that animals might have rational thought process then you might not be wrong, but to apply that in the choice E, you need to put it as an outside assumption.
Since you have to make an outside assumption to reject the option, your rejection most probably be false. Therefore, we should refrain from making any assumption of these kind while answer choice elimination.
B,C and D are obvious out of scope.
A - It is too extreme as it directly tries to challenge Kant's theory rather than undermining it's use by the author.
Hope it helped

It is the central tenet of the ethical theory of the German Idealist

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It is the central tenet of the ethical theory of the German Idealist

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