The question goes like this
P: My daddy loves turnips but not potatoes
C: it is true not that everyone who loves potatoes loves turnips
It is a parallel flaw question, so it is important to find a flaw first.
Q1. Is it a sufficient/necessary flaw? I cannot identify the flaw. Is this a common flaw that frequently appears on flaw question?
Q2. If the conclusion were to say "it is not true that everyone who loves turnips loves potatoes", is this argument valid? I feel that this question is similar to "affirm the sufficient condition, deny the necessary condition" Still confused even though it is very short and looks simple...
I do not know whether I can diagram premise and conclusion. Anyone can clarify on this?
Thank you so much!
Prep 36, Sec 3, Q 19: Parallel Flaw Forum
- suspicious android
- Posts: 919
- Joined: Tue Feb 09, 2010 4:54 pm
Re: Prep 36, Sec 3, Q 19: Parallel Flaw
You have a bit of an error in your quote, make sure you're reading the original correctly.
So the argument is essentially:
P: T & ~P
------------
C: ~(P-->T)
This argument attempts to disprove a conditional statement. The only way to disprove a conditional is to show the sufficient condition can occur without the necessary condition, that is, to show that the proposed necessary condition is not really necessary.
How to disprove the idea that potatoe lovers all love turnips (P -->T)? Show a potatoe lover who doesn't like turnips. The premise is the opposite of that. So it's essentially confusing necessary and sufficient conditions, but also testing you on recognizing how to contradict a conditional statement, which is not particularly common.
Q2: Yes.
So the argument is essentially:
P: T & ~P
------------
C: ~(P-->T)
This argument attempts to disprove a conditional statement. The only way to disprove a conditional is to show the sufficient condition can occur without the necessary condition, that is, to show that the proposed necessary condition is not really necessary.
How to disprove the idea that potatoe lovers all love turnips (P -->T)? Show a potatoe lover who doesn't like turnips. The premise is the opposite of that. So it's essentially confusing necessary and sufficient conditions, but also testing you on recognizing how to contradict a conditional statement, which is not particularly common.
Q2: Yes.
- lovejopd
- Posts: 544
- Joined: Tue Dec 01, 2009 1:00 pm
Re: Prep 36, Sec 3, Q 19: Parallel Flaw
Yeah! Now it is crystal-clear!
Thank you!!
Thank you!!