## How do you know or can ensure when formal logic should be...

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CardozoLaw09

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Joined: Sat Aug 28, 2010 1:58 pm

### How do you know or can ensure when formal logic should be...

applied to a given question? Basically, what are essential things to consider when reading a stimulus that trigger you to notate formal logic beside the stimulus? Obviously, "if..then" statements are the usual indicators of conditional statements, but should you always apply formal logic to these statements? Sometimes it might just distract you if the question doesn't require a formal logic analysis; how do you know when it does or doesn't?
Last edited by CardozoLaw09 on Fri Jul 13, 2012 5:22 pm, edited 1 time in total.

dowu

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Joined: Wed Mar 28, 2012 9:47 pm

### Re: How do you know or can ensure when formal logic should be...

CardozoLaw09 wrote:applied to a given question? Basically, what are essential things to consider when reading a stimulus that trigger you to notate formal logic beside the stimulus?

I see it a lot in must be true, cannot be true and sufficient assumption questions, most often.

The way I see it, is if a conditional statement is present, you should diagram it. They're usually there for a reason, i.e., to play on your knowledge of necessary v. sufficient.

cc.celina

Posts: 602
Joined: Fri May 25, 2012 1:17 pm

### Re: How do you know or can ensure when formal logic should be...

nmop_apisdn wrote:The way I see it, is if a conditional statement is present, you should diagram it.

Tcr. You might not always need your diagram to pick an answer choice, but it takes like 1.5 seconds.

totaltest.milan

Posts: 84
Joined: Mon Feb 14, 2011 9:45 pm

### Re: How do you know or can ensure when formal logic should be...

nmop_apisdn wrote:I see it a lot in must be true, cannot be true and sufficient assumption questions, most often.

That's true. Formal logic appears in what I call 'inference' (must be true) and 'logical conclusion' (sufficient assumption - 'which of the following makes the conclusion follow logically?', 'which of the following justifies the conclusion?', etc). And 'can't be true' questions to some extent.

I teach a different approach to formal logic questions that's based more on Venn diagrams, but the basic way of determining if you're dealing with formal logic is to look for the logical qualifiers: all, none, some, some are not, most, most are not. And the language in the argument will be more formulaic and repetitive.

Diagramming conditionals whenever you recognize them is also a good idea. Train yourself to be sensitive to the sufficiency and necessity indicators along with their synonyms.

dingbat

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Joined: Wed Jan 11, 2012 9:12 pm

### Re: How do you know or can ensure when formal logic should be...

JohnV

Posts: 279
Joined: Sat Jan 02, 2010 8:29 am

### Re: How do you know or can ensure when formal logic should be...

I know it's formal logic when I read it and it immediately confuses the hell out of me.