#24 - One is likely to feel comfortable approaching a

[KelseyWoods]

Hi Hanna!

The conclusion is that "long-term friends are probably of the same approximate age" so the characteristic that the author is inferring is present is "being the same approximate age" not "feeling comfortable approaching if the same age." Also the author does not infer that a characteristic is definitely present based on a premise that it's usually present--which is the flaw that answer choice (B) is describing. Instead, the conclusion says that the characteristic (being the same approximate age) is "probably" present. So our argument does not fit the flaw described by answer choice (B).

Hope this helps!

Best,
Kelsey

[hrhyoo]

Hi Kelsey,

Isn't "most" same as "probable"? B doesn't say definitely, it says "most."

Also, I have another question regarding formal logic:

This question is mistaken reversal because the stimulus states

A -> B
C -> B
THEREFORE C -> A

What if the argument was like the following:

A -> B
C -> B
Therefore A -> C

What kind of flaw is this?

Thank you always!


Hanna

[James Finch]

Hi Hanna,

To answer your questions, yes, "probable" in this case is the same as "most", as it means "more likely than not". As for your second scenario, when we have a chain issue where the stimulus gives us two conditional statements that share the same necessary condition but have different sufficient conditions, and tries to conclude one of the sufficient conditions is actually a necessary condition of the other sufficient condition, this is a form of mistaken reversal. It doesn't matter which of the two is chosen; for your scenario, it could be either either C or A, and it would still be the same logical fallacy committed, as both are essentially logically equal as sufficient conditions for the necessary condition B. Diagramming them together might clarify this:

Premises: C or A B

Conclusion: C A or A C both share the same problem of trying to connect sufficient conditions in an invalid manner

Hope this clears things up!

[hrhyoo]

Thank you James! Could you also explain why B is incorrect?

H

[Zach Foreman]

hryoo,
Most fundamentally, it is incorrect because it doesn't fit our prephrase, "just because you are comfortable approaching same-aged strangers doesn't mean you must be UNCOMFORTABLE approaching different-aged strangers."
B can be paraphrased as "most things of this type have quality X therefore this thing has quality X". If that were applied here it would be something like "Most long term friendships are of similar age to one another. Therefore John's long term friend must be of similar age to him." But that is clearly not what is happening in this stimulus. Hope that helps.

[Dancingbambarina]

I am really struggling with this part of the explanation as I am missing something.

""""
One sometimes approaches strangers even if one does not feel
comfortable doing so.

This statement would neither support nor weaken the conclusion of the argument, because merely
approaching strangers is not something that necessarily leads to long-term friendships; feeling
comfortable approaching a stranger does.
"""""

How do we arrive at the last line "feeling comfortable approaching a stranger does. " when feeling comfortable is the necessary condition of the original conditional in the first line? How do we deduce it to now being sufficient in "leading to" long-term friendships?

Thanks very much

[Adam Tyson]

Look again at the last line of the stimulus:

most long-term friendships begin because someone felt comfortable approaching a stranger.

That's a causal claim, not conditional. Someone feeling comfortable approaching a stranger caused the friendship to begin.