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How would you guys translate this stimulus from words into symbolic logic?
Barf (SpaceBalls movie character) only goes to the ocean on clear nights, and tonight is quite a clear night. Thus, we can conclude that Barf is going to the ocean tonight.
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8 comments
@alexandershort4891 -
I have to agree with @jinadarcy0610262 on this one. Only indicates necessity in this situation. It does not establish that a clear night is sufficient to guarantee he will go to the ocean.
@alexandershort4891 I don't agree with your designation of necessary and sufficient conditions for this statement. The way you diagrammed it, with CN as the sufficient condition, leaves open the possibility that Barf could go to the ocean (GOT) on a night that was NOT clear, because you can deny the sufficient and still have the necessary. That is not what the phrase says.
In this phrase, as in others, the "only" that designates the necessary condition idea is not conveniently placed directly in front of it, but just think about it this way: If it is NOT a clear night, is Barf going to the ocean? No. Because he only goes on clear nights. /CN->/GOT therefore GOT->CN.
The entire argument is invalid as well (mistaken reversal or whatever one prefers to call it).
First, Analytical Reasoning is Logic Games and this appears to be the stimulus for a Logical Reasoning argument. Just a heads up.
Is this a real LSAT question? Just doesn't read like one, but anyway, with either of the statements you mentioned:
Barf only (or always) goes to the ocean on clear nights, and tonight is quite a clear night. Thus, we can conclude that Barf is going to the ocean tonight.
perhaps it's too late, but for some reason, despite understanding the 'only' indicating necessity, it is reading like this:
If it is a clear night (CN), then Barf goes to the ocean tonight (GOT). [CN --> GOT]. It is a clear night. [CN] Therefore, he is going to the ocean tonight. [GOT]
It appeared like a N/S conflation at first, but I think the word-placement just threw me off, and now I've written my thoughts out onto this post.
edit: thanks for the explanation, guys!
It would have been a valid argument if the stimulus stated that Barf ALWAYS goes to the ocean on clear nights.
This is exactly what I was looking for...
B > N
N
...
B
Thanks guys!
paraphrase it in your brain this way:
Barf goes to the ocean only if it is a clear night
It is a clear night
...
Barf goes to the ocean
Symbolize it this way:
B > N
N
...
B
THIS IS AN INVALID ARGUMENT
GO=goes to ocean, CN=clear night
GO implies CN
CN
Therefore, GO
By the way, this is sufficient/necessity confusion.
Edit: Cool. Glad you know it's flawed :)
Is this a flawed argument?
PS -I know this is an invalid conclusion, but I still want to see what the formal logic looks like. Thanks!