3.17 - Strengthen

Strengthen questions can be some of the toughest on Logical Reasoning, especially early on in your studies when you're ratcheting up your understanding of arguments.

Strengthener's tend to look like this:

• Which one of the following, if true, would most strengthen the argument? 
• Which one of the following, if true, adds the most support for the scientists' conclusion?
• Each of the following, if true, supports the claim above except?

The task's in the name. Your job on these questions is to make the argument stronger. And that's principally why these questions can be tough. Lots of things can strengthen an argument, even a tiny amount.

Recall from our earlier lesson that we strengthen arguments by adding support for their conclusions. The right answer choice will add evidence that improves the odds that the conclusion is true, up to and including proving the conclusion entirely (i.e., a sufficient assumption). The wrong answers will either weaken the conclusion or won't affect the argument.

Getting these questions correct depends on your ability to spot conclusions, understand what evidence you have so far, and carefully considering whether an answer choice moves the needle in the argument's favor.

There's some nuance here. Occasionally (often on questions that include the work except), a correct answer will be something that simply doesn't weaken the argument. You'll hear us call this a defensive strengthener. In other words, it's a strengthener by virtue that it isn't a weakener.

Let's look at some examples.

Examples

June 2007 PrepTest, Section 3, Question 13

First, let's look at Question 13 from Test J, Section 3:

Therapist: Cognitive psychotherapy focuses on changing a patient's conscious beliefs. Thus, cognitive psychotherapy is likely to be more effective at helping patients overcome psychological problems than are forms of psychotherapy that focus on changing unconscious beliefs and desires, since only conscious beliefs are under the patient's direct conscious control.

This argument presents a little awkwardly, so let's untangle it. Rephrased, it goes something like this: Only conscious beliefs are under patients' direct conscious control. Cognitive psychotherapy focuses on changing patients' conscious beliefs. Therefore, cognitive psychotherapy is likely to be more effective at helping patients overcome psychological problems than psychotherapies that focus on unconscious beliefs and desires.

Let's tackle these answer choices one at a time.

Answer choice A stinks. If anything, it weakens the therapist's conclusion, working in favor of psychotherapies that focus on unconscious beliefs.

B looks solid. If it's indeed difficult for any psychotherapy to be effective without focusing on things under patients' direct conscious control, then the psychotherapies that focus this direction are likely to be better than those that don't.

C's no good. Even if cognitive psychotherapy is the only form that focuses on conscious beliefs, that doesn't make it more likely that it'll be more effective than alternative psychotherapies.

D's a total trap—it had me in the first half, not gonna lie. It adds a necessary condition to the effectiveness of the unconscious-focused psychotherapies, which would make them less likely to be effective than their counterparts in the abstract (since adding that condition raises the bar / makes it harder to meet all conditions). BUT, do we know whether or not these other therapies meet this new condition even if we grant it as true? No, we don't. So D's out.

E's no good, either. All our conscious beliefs are under conscious control, but other psychological states can't be controlled without therapy? Cool, but who cares? This doesn't impact the likelihood that one therapy is likely to be more effective than others.

June 2007 PrepTest, Section 2, Question 19

Next, let's look at Question 19 from Test J, Section 2:

Historian: The Land Party, achieved its only national victory in Banestria in 1935. It received most of its support that year in rural and semirural areas, where the bulk of Banestria's population lived at the time. The economic woes of the years surrounding that election hit agricultural and small business interests the hardest, and the Land Party specifically targeted those groups in 1935. I conclude that the success of the Land Party that year was due to the combination of the Land Party's specifically addressing the concerns of these groups and the depth of the economic problems people in these groups were facing.

This question includes that pesky word except so we're looking for the answer choice that doesn't strengthen the argument. This could mean it weakens the argument or that it's out of scope altogether.

Start with the historian's conclusion: The Land Party's success in 1935 was due to their focus on the significant economic woes of agricultural and small business interest groups. Next, the support: The Land Party's only national victory was in 1935, most of its support that year came from rural and rural-ish areas, and times were tough in the years around the 1935 election.

Next, let's attack some answer choices. Remember, it's an except question—we need the one that doesn't help the historian's conclusion.

Let's go answer by answer on this one.

Answer choice A looks pretty good off the bat. It reads "In preceding elections the Land Party made no attempt to address the interests of economically distressed urban groups." 

My initial reaction was, "Who cares what happened in preceding elections, especially with the urban populace?" That is, the argument concerns itself with the 1935 election and where the Land Party's support came from. This answer choice is out of scope, so it's almost definitely correct. I'm reading B through E even more skeptically than usual.

B totally strengthens the argument. It reads, "Voters are more likely to vote for a political party that focuses on their problems." If this is true, it helps explain why the special interest groups voted with the Land Party in '35—the party focused on their issues.

C helps too. If the Land Party had most of its success during times of agricultural distress, then they would have had success in 1935, when we're told explicitly that there was economic distress in the agricultural sector.

D strengthens. If no other party in Banestria gave voice to the issues of semirural citizens, it's no wonder they voted with the Land Party.

E strengthens too. If the more economic distress we're in, the more likely we are to vote, then it makes sense that people came out in droves during this era of economic instability.

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That's it for Strengthen questions. Next up, we're wrestling with their twin: Weaken questions. I'll see you there.