Q22 - From time to time

[LukeM22]

Negating (E) means some predatory pricing that leads to unreasonable prices is acceptable. (We know that because that's what negating it tells us. That's the point of negating it.) If that's true, the argument would not hold. Negating (E) destroys the argument.

Like a number of other posters I crossed off E because it struck me too much as a sufficient assumption (which it apparently is, in addition to being necessary).

Assuming the above is the correct way to negate E, how exactly does this kill the argument? It's perfectly possible for the practice to be acceptable even in a universe where other "do not result in unreasonable prices" policies are unacceptable. Weakens? Yes. Kills? Doesn't seem like it. It is not necessary for every single policy with that attribute to be acceptable; only for that one to be acceptable, or at least have the possibility of being acceptable.

Now, if E was "at least some pricing practices that do not result in unreasonable prices should be acceptable", and whose negation would therefore be "no pricing practices that do not result in unreasonable prices should be acceptable", then, yeah, that kills the argument, because no further information is needed to know that it's impossible for this policy to ever be acceptable given what we know about it.

But it doesn't strike me as necessary for the entire universe of policies with similar traits to be accceptable for the conclusion to follow.

[ohthatpatrick]

I agree with you. The correct answer is stronger than it needs to be. That seems to be a growing trend on recent tests for Necessary Assumption.

Conditional logic answers used to almost always be wrong, but now they're often correct. Basically, the test seems to be thinking, if an author makes a certain move from one idea to another, then we are allowed to say he must be assuming some black and white rule.

If the author thinks that "knowing the threat of competition will keep the company from reaching unreasonable prices" is all we need to consider in order to judge, with certainty, that "this practice clearly should be acceptable", then the author must be assuming that avoiding unreasonable prices is always enough to justify that a pricing practice is reasonable.

(By the way, the negation of this is also not what has been written in much of this thread --- negating a conditional always means "there's at least one counterexample where something IS the left side but ISN'T the right side".

So negating (E) only gives us "some pricing practices that avoid unreasonable prices should NOT be accepted". That doesn't feel like a super powerful objection.)

So, in summary, these correct conditional logic answers on Necessary Assumption will likely bother you in two ways:
- they seem stronger than they need to be
- because of that, negating them doesn't feel like the normal "drop a piano on the author's head" type of objection

My advice is that when we see a conditional answer choice on Necessary Assumption, we just ask ourselves:
1. In the argument, did the author make this move? (beware: illegal reversals and negations, which are super common in conditional answer choices)

2. Did the author make this move with certainty.

If the answer is yes to both of those, then we should definitely consider picking that answer.

Hope this helps.

[M.M.]

Here, I'll walk through the whole thing.

The core is:

The mere threat of renewed competition will keep the companies that engaged in "predatory pricing" from raising their prices

-->

Predatory pricing is acceptable

What's the assumption here? Well...how do we know there is going to even be a threat? And where did we ever see a definition of what is "acceptable?" There's no particular reason given for why certain prices are acceptable.

(A) seems pretty good... If we negate it to read, "Some companies that are successful won't necessarily induce competitors to enter the market," then does it destroy our argument? Well, it depends. Are these companies successful or not? What makes a company successful? And wait, do we really need competitors to enter the market? No, we just need the THREAT of it. (A) is out.

(B) doesn't matter. So what? Even if they do it one at a time, the question is whether it's acceptable.

(C) is like (C). Fine, but is it acceptable or not? Is there a threat?

(D) isn't necessary. If we negate it, "It is NOT only the threat of competition or competition that keeps companies from raising prices," is our conclusion destroyed? No, actually, it's stronger! There might be other reasons predatory pricing is fine, too. Great.

(E) ANY pricing practice? Does this seem overly broad? Well, not if we look back at what the argument is saying. It's saying that if the company doesn't raise its prices thanks to the threat of competition, then what it's doing should be acceptable. If we negate (E) to read, "Some pricing practices that don't result in unreasonable prices should not be acceptable," yikes, our argument crumbles, because how do we know this practice is not one of those? The argument doesn't make sense anymore.

(E) is correct.

Hope this helped clarify.

Why would we add two "nots" to E upon negating it? My thought of how it would look if negated is "some pricing practices that do not result in unreasonable prices should be acceptable" - which does seem to seriously hurt the argument, but not quite destroy it, and I ended up choosing it because it was the most attractive of the answer choices, but you've added "should NOT be acceptable" which is another negation *and* also suffers from the same problem as just the single negation that I posed before, where it leaves open the possibility that this is one of those that should be acceptable.