## Conditional Q

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lovejopd

Posts: 544
Joined: Tue Dec 01, 2009 1:00 pm

### Conditional Q

Hello,

How can I correctly diagram this sentence?

A then B unless C
--> Baterial species will develop resistance unless antibiotics kill all species
(Q. from Prep 62 Sec 4, Q 11.)

Is it
~C+A --> B
or
~C-->(A-->B)

Thx!

Daily_Double

Posts: 1031
Joined: Tue Dec 04, 2012 8:45 pm

### Re: Conditional Q

(A --> ~B) ---> C

~C ---(A ---> B)

But it's really easier than that, I wouldn't even diagram it. It breaks down to if batteries don't do this then kill everything. If not kill everything, then batteries do this. This is from memory so I'm not quoting it precisely.

objection_your_honor

Posts: 625
Joined: Sat Feb 11, 2012 2:19 pm

### Re: Conditional Q

You really only need two terms for this question.

Species develops greater resistance --> antibiotics eliminate species

So given that there is no antibiotic out there strong enough to eliminate the species, we know per the contrapositive that the species will develop a greater resistance against any antibiotic used against it.

lovejopd

Posts: 544
Joined: Tue Dec 01, 2009 1:00 pm

### Re: Conditional Q

Oh...Thank you...

How would you diagram the first sentence of Prep 62, Section 4 Q. 18 I am always confused by this structure of sentence...
If A, Not B unless C

Should it be....

Sentient beings(A) ---> (Determine(B) --> as intelligent as humans(C))

OR

~as intelligent as humans(~C) --> (Sentient beings(A) --> ~ Determine(~B))

Plz...Help
Last edited by lovejopd on Thu May 30, 2013 11:03 pm, edited 1 time in total.

mvonh001

Posts: 581
Joined: Wed Mar 28, 2012 3:49 pm

### Re: Conditional Q

Why do you put parentheses around the variables? (A+B)-->C would mean what as compared to
A+B-->C

lovejopd

Posts: 544
Joined: Tue Dec 01, 2009 1:00 pm

### Re: Conditional Q

mvonh001 wrote:Why do you put parentheses around the variables? (A+B)-->C would mean what as compared to
A+B-->C

Because I am not sure how 'unless' plays a role in a setence....

mvonh001

Posts: 581
Joined: Wed Mar 28, 2012 3:49 pm

### Re: Conditional Q

I wasnt asking you specifically with regards to the example you posted. I was referring to the general act of putting parentheses around variables in an argument.

objection_your_honor

Posts: 625
Joined: Sat Feb 11, 2012 2:19 pm

### Re: Conditional Q

lovejopd wrote:Oh...Thank you...

How would you diagram the first sentence of Prep 62, Section 4 Q. 18 I am always confused by this structure of sentence...
If A, Not B unless C

Should it be....

Sentient beings(A) ---> (Determine(B) --> as intelligent as humans(C))

OR

~as intelligent as humans(~C) --> (Sentient beings(A) --> ~ Determine(~B))

Plz...Help

Revisit Powerscore's Logical Reasoning Bible and read the section on what they call the "unless equation." There should be some drills with it. Generally, whatever comes before "unless" is the negated sufficient condition, and whatever comes after "unless" is the necessary condition.

bp shinners

Posts: 3086
Joined: Wed Mar 16, 2011 7:05 pm

### Re: Conditional Q

lovejopd wrote:Oh...Thank you...

How would you diagram the first sentence of Prep 62, Section 4 Q. 18

For this one, I wouldn't worry about the sentient beings in the diagram - they're a predicate for the entire argument to work. If there aren't sentient beings, then the whole argument is pointless. That first "If there are..." is just there to set up that we're talking about a world where we assume they exist.

But, were I to diagram it, I would do:
SBPOSS AND ~AIHumans -> ~Determine

You could also do:
SB -> (~AIHumans -> ~Determine)
The parentheses here means that the parenthetical conditional is just the necessary condition; and it's not transitive. Without the parentheses, it would mean "If there are aliens, then they are not as intelligent as humans, and then we can't determine they exist." With the parentheses, it means if there are aliens, then them not being as intelligent as humans is sufficient to tell me we can't determine their existence. Subtle difference.

In both cases, however, the argument revolves around the assumption that aliens exist, because otherwise there's no point to talking about how we're going to find them. So I wouldn't even worry about it, and just take "If aliens exist..." as background.