#10 - It is a principle of economics that a nation can

[shanikaduverneau]

Hi! I'm having a little trouble understanding the LRB's reasoning as to why answer D is correct.

The stimulus states: "It's a principle of economics that a nation can experience economic growth only when consumer confidence is balanced with a small amount of consumer skepticism".

I chose answer choice A, but understand why it's incorrect due to it being a mistaken reversal. However, the LRB says that answer choice D is correct because it "forces us to recognize that the negation of "consumer confidence is balanced with a small amount of consumer skepticism" is phrased as "prevailing attitude of consumers is exclusively confidence"". I'm having trouble understanding why that would be the negation in we're working through this problem. Wouldn't the negation be that it is almost exclusively?

[Jeff Wren]

Hi shanikaduverneau,

The necessary condition that "consumer confidence is balanced with a small amount of consumer skepticism" means that both consumer confidence and consumer skepticism are necessary for a nation to experience economic growth. In addition, it's not simply enough to have both of these terms (confidence and skepticism), but they must be "balanced." In other words, if they're aren't balanced exactly right, (such as having too much confidence or too much skepticism), then economic growth won't happen for a nation.

To use the contrapositive, we need to know that "consumer confidence is not balanced with a small amount of consumer skepticism." However, there are many ways that this situation could be expressed. Perhaps we have consumer confidence but no consumer skepticism, or perhaps we have consumer skepticism but no consumer confidence, or perhaps we have both elements but in the wrong proportions. Any of these would indicate that "consumer confidence is not balanced with a small amount of consumer skepticism" and would trigger the contrapositive. Here, Answer D, by stating that consumers are "exclusively confident," indicates that there is no small amount of consumer skepticism to balance the confidence out, which means that they are not balanced as required by the original necessary condition.

[vprta121]

I am just a little confused on the contrapositive of this example.

if we established that eg --> ccb then the we know that the sufficient condition is eg and the necessary condition is ccb. For the contrapositive we would have (not ccb ---> not eg) so does that mean the sufficient condition is now "not ccb" and the necessary condition is "not eg"?

I'm between answer a) and d) because I cannot identify what is the sufficient condition and what is the necessary condition in the answer choices.

[Amber Thomas]

Hi vprta121!

We can set up our conditional relationship as follows:

Economic Growth (EG) --> Consumer Confidence is Balanced with Consumer Skepticism (CCB)

So, our contrapositive would be: ~CCB --> ~EG

You're absolutely right that our new sufficient condition is "Not CCB" and our new necessary condition is "Not EG." How does this play out in our Answer Choices?

Let's look at correct Answer Choice D: "Any nation in which the prevailing attitude of consumers is exclusively confidence will not experience economic growth."

So, "any nation where the prevailing attitude of consumers is exclusively confidence" inherently means that there is NOT a balance between consumer confidence and consumer skepticism, thereby giving us the condition ~CCB! Therefore, Answer Choice D sets up ~CCB --> ~EG, which is exactly what we are looking for!

Now, let's look at Answer Choice A: "Any nation in which consumer confidence is balanced with a small amount of consumer skepticism will experience economic growth."

The conditional relationship that this sets up is: CCB --> EG, which is a reversal of our two initial conditions. Remember, we can never just swap our conditions like this; in order to draw a proper contrapositive, we must negate our conditions when we flip them.

I hope this helps!