Is "The only" always a sufficient condition indicator? Forum

[cneu333]

I was going through PT62 and came across the following conditional statement: "The only people whose athlete's foot was cured had been given medication M." I thought this could be diagrammed as [On medication M -> Athlete's foot cured] but I was wrong.. Does "The only" always introduce a sufficient condition regardless of the placement in a sentence, or is that the case only when it is placed in the beginning of the sentence?

[VasaVasori]

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[CardozoLaw09]

So "only the" would introduce a necessary condition? I would've diagrammed the way OP initially did as well.

[VasaVasori]

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[CardozoLaw09]

Perfect, thanks!

[Verity]

It means "if you're athlete's foot was cured, you had been given the medication."

Athlete's foot cured --> on medication

You got it backwards. You're saying that anyone on the medication had their athlete's foot cured.

[cneu333]

Wow, that was very helpful. Thank you so much! I really appreciate it.
It seems that "The only" is usually used as a sufficient indicator, but could be used as a necessary indicator at times depending on its context and usage.

If I say,

"The only dogs are in this room," you know that anything that is a dog is in this room. If X is a dog, then X is in this room.

So, you would diagram this as "dog -> this room," meaning "the only" indicates a sufficient condition.

Cardozo, you're absolutely right - "only the" would produce the opposite effect. Say we said,

"Only the dogs are in this room." From this statement, we know that anything that is in this room is a dog. if X is in this room, then X is a dog. And so, we would diagram that as "this room -> dog," meaning "only the" indicates a necessary condition.

Does that make sense?

On a side note, I think it's good to know a few of these off the bat, but I personally never straight-up memorized any of them. Once you do enough LR sections, you'll be able to diagram these automatically, not (only) because you've memorized them but also because you've thought about them so much. It's important to be able to reason out what the different phrases mean yourself, because you might encounter an unfamiliar one on the LSAT that you take. Of course, memorizing them might make the problems take less time.

Edit: I was googling to find a list of sufficent and necessary conditions for you, and found a few links:

http://lsatblog.blogspot.com/2009/10/wo ... ssary.html
http://www.flashcardexchange.com/cards/ ... ors-653537

More importantly, I found this thread, wherein someone points out that phrases like this containing "the only" may not necessarily trigger a sufficient condition (but this is also used in a very different way):

If we win the only possible outcome is that they lose.

[PDaddy]

I was going through PT62 and came across the following conditional statement: "The only people whose athlete's foot was cured had been given medication M." I thought this could be diagrammed as [On medication M -> Athlete's foot cured] but I was wrong.. Does "The only" always introduce a sufficient condition regardless of the placement in a sentence, or is that the case only when it is placed in the beginning of the sentence?

You have it backwards. "Only" will normally introduce a necessary condition. Still, the word "Only" does NOT always introduce the necessary condition. Its placement can affect the condition. Starting a sentence off with "The only" just means that one can remove "only" from the sentence without altering the meaning of the sentence.

"The only people whose athlete's foot was cured had been given medication M." So it reads: IF their athlete's foot was cured, THEN they were given Medication M.

If I have money I will go to the store. This is classic "If-Then" form, where the "If" intorduces the Suff. Condition.

If only I have money, I would go to the store: Suff = Money. The "only" is redundant in this case and can be omitted as a result, and the "If" introduces the sufficient condition.

Only if I have money will I go to the store: Nec = Money. If I went to the store, you know that I have money.

I will go to the store only if I have money: Nec = Money. This sentence is just like the first example, only with the order of the conditions reversed.

The only people who went to the store had money: Nec = Money. If they went to the store, you know they MUST have had money. This is like OP's example. If their athlete's foot was cured, you know they MUST have received Medication M.