Q13 - People who say that Dooney County is flat

[mornincounselor]

DC --> ~F
F --> ~SE
F --> ~T
DC --> T


(A)
W--> S --> PA
----------------
~W

(B)
C --> +space
~C--> +$$

(C)

E --> ~T
E --> ~M
M--->~E

(D)
S when H --> SF --> CRE
--------------------
~LW

(E) People who have f tend to need c
------------------
F-->C

[ohthatpatrick]

Nice work! I will suggest a few tweaks, but you did a great job overall of sizing up the logic of all these.

I don't think I would represent the first sentence as
DC --> ~F

If it's Dooney County, then it's not flat?

The first sentence isn't a conditional idea, it's a statement of fact.

People are wrong to say that DC is flat.

How do you rephrase that as the author's opinion?

DC is NOT flat.

If I'm trying to diagram this, I would represent a statement of fact as
DC = ~flat.

Similarly, you represented the last sentence as conditional. Again, the last sentence is just a statement of 'fact' (it's hearsay, but it's still a secondhand fact, not a secondhand conditional).

What's the fact in the final sentence?

DC = terraces.

Finally, in a couple of these arguments, the author uses "consequently" or "hence" to chain a third factor onto the second one.

In the original, for example, the author says "erosion is not a problem, consequently, they don't build terraces".

I would interpret those two sentences as
Flat --> ~Erosion problem --> ~build terraces

So my original argument would look like
F --> ~EP --> ~T
DC = T.
------------
DC = ~F.

I would be looking, in a correct answer choice, for something that game a conditional chain of 3 things, provided a statement of fact about something specific that contradicted the end of the chain (activating the contrapositive), and correctly concluded that the first part of the chain would not be true about this specific something.

(C)
Exercise -> no trouble sleeping -> no medication
Jack = medication
----------
Jack = ~Exercise

Hope this helps.

[roflcoptersoisoi]

Structure of the argument:

Flat ---> ~ SEWP
----------------------
Flat ---> ~ FBTPE

FBT
----------------
~ Flat


(A) This argument is missing a premise and the conclusion is prescriptive, not descriptive like the one in the argument.
The structure of this argument is:

W --> S
W---> PAS
-------------
~W

This would be correct if the argument was structures like so:

W ---> S
W --> PAS
~ PAS '

------------
~W

Note the bolded, premise that is missing from the answer choice.

(B) This contains a comparative premise, the original argument doesn't. It's also missing a couple premises. I stopped reading after the first sentence.

(C) Bingo.

Structure:

ES --> ~TS
ES --> UMHs
UM
-----------------
~ES

(D) Similar to (A) it's missing a premise.

(E) Conclusion mismatch (the conclusion is a conditional statement) it's also missing a premise.

MF --> O
--------------
O --> C
---------------
MF --> BC

[AlexM563]

Isn't C still flawed reasoning? It took me a while to pick it. Just because Jack is taking many kinds of medication doesn't mean that he is taking any medication which helps him fall asleep.

[hzj184]

Isn't C still flawed reasoning? It took me a while to pick it. Just because Jack is taking many kinds of medication doesn't mean that he is taking any medication which helps him fall asleep.

a is normative conclusion, so it must be eliminated
e is a conditional conclusion, so it must be eliminated
b is out of scope
d brings a new idea (fat) to the conclusion, which is different from the stimulus

stimulus:
conclusion: not flat
premise: flat —> soil erosion is not a problem
flat —> do not build terraces to prevent soil erosion
build terraces —> flat

c:
conclusion: NOT a lot of exercise
a lot of exercise —> no trouble sleep
a lot of exercise —> no medication to help fall asleep
medication —> NOT a lot of exercise

c matches the same flawed reasoning structure