LSAT Question Stem

The argument is most vulnerable to criticism on the grounds that it 

Logical Reasoning Question Type

This is a Flaw question. 

Correct Answer

The correct answer to this question is A. 

LSAT Question Complete Explanation

Let's break down the argument in the passage and analyze its structure. The argument begins with a claim made by some statisticians about the surest way to increase the overall correctness of one's beliefs: never change the set of beliefs, except by rejecting a belief when given adequate evidence against it. The author then argues that if this were the only rule one followed, one would either have to reject some beliefs or leave them unchanged when presented with any kind of evidence. Over time, this would lead to having fewer and fewer beliefs. The author concludes that since we need many beliefs to survive, the statisticians' claim must be mistaken.

In this argument, the author's main conclusion is that the statisticians' claim is mistaken. The premises supporting this conclusion are: (1) if this rule were followed, one would either reject beliefs or leave them unchanged when presented with evidence, and (2) we need many beliefs to survive.

An "Evaluate" question for this argument could be: "Does the need for many beliefs to survive necessarily mean that the statisticians' claim about increasing the overall correctness of one's beliefs is mistaken?"

Now, let's discuss the question type and the answer choices. The question type is a Flaw question, asking us to identify the grounds on which the argument is most vulnerable to criticism.

a) This answer choice is correct. The argument presumes without providing any justification that the surest way of increasing the overall correctness of one's beliefs must not hinder one's ability to survive. The author assumes that if the statisticians' claim were correct, it would hinder survival, and therefore, it must be mistaken. However, this assumption is not necessarily true, and the argument is vulnerable to criticism on this point.

b) This answer choice is incorrect. The argument does not neglect the possibility of accepting new beliefs while following the statisticians' rule. The rule itself explicitly states that one should only reject a belief when given adequate evidence against it, which implies that one could still accept new beliefs when presented with evidence.

c) This answer choice is incorrect. The argument does not overlook the possibility that some large sets of beliefs are more correct overall than some small sets of beliefs. The author's concern is about the decreasing number of beliefs over time, not about the relative correctness of different sets of beliefs.

d) This answer choice is incorrect. The argument does not take for granted that one should accept some beliefs related to survival even when given adequate evidence against them. The author's focus is on the decreasing number of beliefs over time and the need for many beliefs to survive, not on the specific content of the beliefs.

e) This answer choice is incorrect. The argument does not take for granted that the beliefs we need in order to have many beliefs must all be correct beliefs. The author's concern is about the decreasing number of beliefs over time and the need for many beliefs to survive, not about the correctness of all the beliefs we have.

In conclusion, the correct answer is choice A. The argument is most vulnerable to criticism on the grounds that it presumes, without providing any justification, that the surest way of increasing the overall correctness of the total set of one's beliefs must not hinder one's ability to survive.