Logical Reasoning

PT111 · S1 · Q23 Some statisticians claim that the

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Some statisticians claim that the surest way to increase the overall correctness of the total set of one’s beliefs is: never change that set, except by rejecting a belief when given adequate evidence against it.

Conclusion

The statisticians' claim must be mistaken. i.e. The surest way to increase the overall correctness of the total set of your beliefs is not to stop adding beliefs and discard any belief you have adequate evidence against.

Evidence

If this were the only rule you followed, you'd have fewer and fewer beliefs over time. And we need many beliefs in order to survive.

Evaluate

This seems like one of those Flaw questions where the author's rebuttal is just irrelevant to the original position.

The original position is about . The author rejects this way, but it doesn't seem like he proposes an alternative method that would be a surer way to increase the overall correctness of your beliefs.

Instead, he just talks about how many beliefs one needs to survive, which doesn't seem like it's even on topic. Who was talking survival? The statisticians were only talking about the correctness of one's belief set (it was an abstract mathematical point, not advice for living).

In case their math isn't making sense, suppose you had 10 beliefs, 5 true and 5 false. Right now the overall correctness of your belief set is 50%. You're never adding beliefs, but you can get rid of beliefs. If you find out 2 of your 10 beliefs are false, you get rid of them, and now you have 5 true and 3 false beliefs. The overall correctness of your belief set went from 5/10 to 5/8, or from 50% correct to 62.5% correct.

The more false beliefs you get eliminate, the closer you'll get to 100% correctness for your belief set. And since adding beliefs could potentially lower the correctness of your belief set (if you added a false belief), the statisticians are making a boring abstract argument that by only getting rid of bad apples, the percentage of good apples in your barrel would always be rising.

Goal

Look for an answer pointing out the author's irrelevant rebuttal. He hasn't said anything to dispute the statisticians' claim that this method would be sure to increase the overall correctness of your belief set.

He seem to be concerned that following this method would imperil your chances of survival, but that doesn't go against the truth of the statisticians' claim. They didn't say we should adopt this way of living. If someone died from having too-few beliefs, but those beliefs had a super high rate of overall correctness, then the statisticians' claim would still be true.

23.

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

Correct
presumes, without providing any justification,
Why this is right
When Flaw answers start with takes for granted / presumes / fails to establish, we can ask ourselves whether the author was really assuming the idea that follows. Since this idea is conditional, we could look at it conditionally and see if it matches a move the author made: IF a way of increasing THEN it's not overall correctness of → the surest way belief set hinders ability to survive Yes, the author did make this assumption. The left side matches the evidence and the right side matches the conclusion. Even if we weren't clear on how to match up this conditional assumption with the author's reasoning move, we still might just pick this answer from its general gist of, "this author is assuming that the surest way of increasing correctness has anything to do with its effects on survival."
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
41% picked this
neglects the possibility that even
Not an Objection
The author does neglect this possibility, but only because it's self-contradictory. This wouldn't be a way for us to object to the author: "Hey, you failed to consider this self-contradictory idea!" The statisticians' rule explicitly said that we would never change our set of beliefs except by rejecting beliefs. So it is impossible to follow the statisticians' rule while also accepting new beliefs.
43% picked this
overlooks the possibility that some
Not an Objection
When Flaw answer choices start off with fails to consider / overlooks the possibility, we can ask ourselves whether the idea that follows would be an objection to the logic. Could we hurt this argument by saying, "Even though following this rule would mean an ever-decreasing number of beliefs, and you need many beliefs to survive, this rule still is the surest way to increase overall correctness because ... at least one large set of beliefs is more correct overall than at least one small set of beliefs"? That doesn't sound like a good objection. And it's very, very rarely the case that a correct weakening idea would be as weak as "some".
3% picked this
takes for granted that one
Too Strong: should accept
This author is only thinking "we shouldn't get rid of all these false beliefs, because then we'll end up with fewer and fewer beliefs, and we need many beliefs to survive." She isn't assuming that "we should add some false beliefs".
4% picked this
takes for granted that the
Too Strong
Too Strong: must all Opposite, if anything The author is saying "we can't reject all these false beliefs, because then we'll have fewer and fewer beliefs, and we need many beliefs to survive". So if anything, the author seems to be thinking we should retain these false beliefs for the sake of our survival, which is the opposite of what this answer accuses her of assuming. Even if this weren't going the opposite direction, we wouldn't feel comfortable accusing the author of assuming something as strong as "all the beliefs must be X".
9% picked this

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