Strengthen and Weaken Arguments
CLAT arguments almost always claim that one thing caused another, and strengthening or weakening them means testing that causal link against alternative explanations.
10 questions · 5 minutes · instant scoring
What this topic actually tests
A strengthen-or-weaken question presents a short argument - usually a claim that some action or event caused a particular outcome - and asks which option, if true, would most support or most undermine that reasoning. The first step is to isolate the argument's actual logical gap, not just its topic. Most CLAT arguments here are causal: they observe that outcome B happened after or alongside action A, and conclude A caused B. This reasoning is vulnerable in three specific ways, each of which maps directly to a strengthening or weakening strategy. First, an alternative cause may explain B just as well - weaken by supplying one (for instance, a seasonal or coincidental factor), strengthen by ruling all such alternatives out. Second, the correlation might run backwards, or both A and B might share a hidden common cause - weaken by showing this, strengthen by showing the timing and mechanism only work in the claimed direction. Third, the evidence might not generalize - an analogy from a trial, a lab study, or another city may not transfer to the real situation being discussed - weaken by showing the analogy breaks down, strengthen by showing the two situations are relevantly similar. Crucially, an option is only correct if it is directly relevant to this causal gap; many wrong options are true-sounding facts about cost, popularity, or side details that neither support nor attack the actual reasoning, and must be set aside as irrelevant. Worked example: 'Sales of umbrellas spiked right after the company launched its ad campaign, so the campaign caused the spike.' An option stating that the spike coincided with the start of the monsoon season directly weakens the argument by supplying a more obvious alternative cause, while an option about the campaign's production cost is simply irrelevant and changes nothing about whether the campaign caused the sales spike.
The common trap on this topic
The most frequent error is picking an option that is merely emotionally or thematically related to the argument's topic without actually engaging its logical gap - for instance, choosing 'employees disliked the new schedule' to weaken a productivity argument, when dislike says nothing about whether productivity actually changed. Aspirants also confuse an argument's premises with its assumptions, and pick an option that merely restates part of the evidence already given rather than adding new information that shifts the probability of the conclusion. Another common mistake is failing to distinguish between weakening an argument's conclusion and simply pointing out a practical difficulty in implementing the recommended action - an option like 'the program would require hiring more staff' does not weaken a causal claim about effectiveness, since feasibility and causation are separate questions. Finally, in analogy-based arguments such as ones drawing conclusions from mice studies or pilot programs, students often overlook the specific option that attacks the transferability of the evidence itself, instead choosing a more generic-sounding option about sample size or cost that is only weakly related to the actual inferential leap being made.
Take the micro-test
Argument: 'The city should ban single-use plastic bags, since other cities that imposed such bans saw a drop in litter and marine pollution.' Which option, if true, most weakens this argument?
Argument: 'Schools should introduce compulsory financial literacy classes, since a survey found most young adults who default on loans never studied basic budgeting in school.' Which option, if true, most strengthens this argument?
Argument: 'Employees who take short breaks every hour report higher productivity scores, so companies should mandate hourly breaks to boost productivity.' Which option, if true, most weakens this argument?
Argument: 'The new traffic signal timing at the Main Street intersection reduced congestion, since average commute times dropped 15% after it was installed.' Which option, if true, most strengthens this argument?
Argument: 'Umbrella sales spiked right after the company launched its new ad campaign, so the campaign must be responsible for the sales increase.' Which option, if true, most weakens this argument?
Argument: 'Switching the office to a four-day work week will not reduce overall output, because a trial at a similar-sized firm in the same industry showed unchanged output after the switch.' Which option, if true, most strengthens this argument?
Argument: 'A new drug reduced tumor size in laboratory mice, so it will likely be effective in treating cancer in humans.' Which option, if true, most weakens this argument?
Argument: 'A company's new employee wellness program is responsible for the recent drop in sick-leave days, since sick leave fell 20% in the six months after the program launched.' Which option, if true, most strengthens this argument?
Argument: 'Raising the minimum wage will increase the standard of living for low-income workers, so the government should raise it immediately.' Which option, if true, most weakens this argument?
Argument: 'A city's decision to install more streetlights reduced night-time crime, since crime reports fell 30% in well-lit areas within a year of installation.' Which option, if true, most strengthens this argument?
FAQ
What is the fastest way to identify the argument's logical gap?
Ask what alternative explanation could account for the same outcome besides the one claimed. If the argument says A caused B, look for a hidden third factor, a reversed causal direction, or a broken analogy - the correct option almost always targets one of these three gaps.
Why are options about cost or difficulty usually wrong answers?
Because strengthen-weaken questions test the logical connection between evidence and conclusion, not the practicality of implementing a proposal. A fact about expense or feasibility does not change whether the causal claim itself is true, so it is usually irrelevant.
How do I handle an argument based on an analogy, like a lab trial applied to real life?
Check whether the two situations being compared are relevantly similar in the ways that matter to the outcome. An option showing they differ in a crucial respect weakens the argument, while an option confirming they share key characteristics strengthens it.
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