## Question about S -> N in this sentence

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ljh912005

Posts: 7
Joined: Thu Aug 09, 2012 7:11 pm

### Question about S -> N in this sentence

How would you diagram this into S->N

Every major war in the last 200 years has been preceded by a short sharp increase in the acquisition of weapons by the nations that subsequently became participants in those conflict.

Isn't it...

Sharp increase in the acquisition of weapons(S) -> every major war in the last 200 years (N)?

This is a question from Oct 03 - LR section 3 question 21.

I diagramed it this way and got the question right.

However, Manhattan LSAT seems to say the other way around... and I reached the correct answer somehow.

http://www.manhattanlsat.com/forums/q23 ... 978eea5fd1

Fianna13

Posts: 297
Joined: Thu Feb 03, 2011 1:05 am

### Re: Question about S -> N in this sentence

every=sufficient.

so Manhattan is right.

LSATdecember2012man

Posts: 22
Joined: Mon Aug 20, 2012 11:06 am

### Re: Question about S -> N in this sentence

Fianna13 wrote:every=sufficient.

so Manhattan is right.

yea, manhattan is right.

Sufficient/Necessary has nothing to do with the order of the events described in the conditioning statement.

Necessary part can come first, after, or at the same time as the sufficient.

Condition statements are just "If you know the sufficent condition exists, you can assume the necessary part has happened before, will happen, or has happened at the same time.

trying to help out the forum after so much help was given to me

Redfactor

Posts: 413
Joined: Fri Jun 10, 2011 8:52 pm

### Re: Question about S -> N in this sentence

ljh912005 wrote:How would you diagram this into S->N

Every major war in the last 200 years has been preceded by a short sharp increase in the acquisition of weapons by the nations that subsequently became participants in those conflict.

Isn't it...

Sharp increase in the acquisition of weapons(S) -> every major war in the last 200 years (N)?

This is a question from Oct 03 - LR section 3 question 21.

I diagramed it this way and got the question right.

However, Manhattan LSAT seems to say the other way around... and I reached the correct answer somehow.

http://www.manhattanlsat.com/forums/q23 ... 978eea5fd1

Stop thinking about tricks and just understand what you're saying.

Sufficient forces the necessary to be true.
Necessary is required if the sufficient is true.

A -> B
IF a THEN b
IF I own a dog (a), THEN I have to take it for walks(b).

------------------------------
(info) I own a dog.

(conclusion) Since I own a dog, we know that I take it for walks even though that information was not given, because owning a dog was SUFFICIENT information to come to that logical conclusion.

-------------------------------

(info) I take a dog for walks.

(conclusion) We know nothing more than that I take a dog for walks. It could be my dog but it could also be someone else's dog. We do not know whose it is.

-------------------------------

(info) I do not take any dogs for walks.

(conclusion) Since walking my dog is a NECESSARY condition of dog ownership, we can conclude that I do not own a dog. Negating a necessary condition negates the sufficient condition. It is the contrapositive and sound logic.

My suggestion is to step away from LSAT questions / tests and just practice non LSAT sufficient / necessary identification. That way you won't use up seeing questions for the first time while you're still struggling with basic proper logic.

John_rizzy_rawls

Posts: 3468
Joined: Sun Nov 18, 2012 2:44 pm

### Re: Question about S -> N in this sentence

Think of what the argument is telling you.

If sharp increase then war? Nope.

It's saying every war has shown sharp increase. That's a logical sufficient trigger.

So that means if war ---> sharp increase.

Trajectory

Posts: 101
Joined: Sat Feb 09, 2013 5:04 pm

### Re: Question about S -> N in this sentence

I didnt read through every single post but just to make sure, after reading your problem and the actual sentence to be diagrammed, the first thing that jumped out at me was that maybe because it says that acquisition in weapons (AIW) "preceded" war (W) you thought that this relationship was applicable to the diagramming and so you put AIW --> W? Clearly through what others have stated so far you can see thats not the case. "Every" triggers the idea of a sufficient condition.

I hope this makes sense. It might not be the way you thought but just in case.

bgdddymtty

Posts: 696
Joined: Thu Feb 11, 2010 12:59 pm

### Re: Question about S -> N in this sentence

I don't have the question in front of me, but one important point: just because something has always happened doesn't mean it will always happen in the future. Every war of the past 200 years may have been preceded by a given condition or event, but it's entirely possible that wars in the future will not be.

Clearly

Posts: 4191
Joined: Sat Feb 11, 2012 4:09 pm

### Re: Question about S -> N in this sentence

Just a heads up, thats question 23, not 21