Question:
Human decision-making relies on cognitive shortcuts known as heuristics. While these shortcuts allow rapid decisions in uncertain situations, they also cause predictable errors. Understanding how heuristics shape judgment can help in designing better decision-making environments.
What is the main idea?
- Heuristics should be eliminated from human thinking.
- Heuristics are more harmful than useful.
- Understanding heuristics helps improve decision systems.
- Human decisions cannot be improved.
Human decision-making relies on cognitive shortcuts known as heuristics. While these shortcuts allow rapid decisions in uncertain situations, they also cause predictable errors. Understanding how heuristics shape judgment can help in designing better decision-making environments.
What is the main idea?
- Heuristics should be eliminated from human thinking.
- Heuristics are more harmful than useful.
- Understanding heuristics helps improve decision systems.
- Human decisions cannot be improved.
Show Hint
Rewrite the passage as a because-but-therefore chain. The correct main idea should keep the balanced contrast and the practical consequence stated after it.
Updated On: Aug 14, 2026
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Approach Solution - 1
Approach: The main idea is the passage's destination, not its starting facts. Read the last sentence \(--\) in tight paragraphs it usually states the purpose.
Step 1: Track the arc. Sentence 1 defines heuristics as cognitive shortcuts. Sentence 2 grants they enable fast decisions but also cause predictable errors (balanced view). Sentence 3 lands the point: understanding how heuristics shape judgment can help design better decision-making environments. That last clause is the takeaway.
Step 2: Match. Option 3 \(--\) "understanding heuristics helps improve decision systems" \(--\) restates that final, purpose-stating sentence exactly.
Step 3: Eliminate. Option 1 ("eliminate heuristics") is too extreme; the passage never asks to remove them. Option 2 ("more harmful than useful") distorts the balanced tone \(--\) the passage credits their usefulness. Option 4 ("decisions cannot be improved") flatly contradicts the optimistic closing line.
Main idea: \( \text{Option 3} \)
Step 1: Track the arc. Sentence 1 defines heuristics as cognitive shortcuts. Sentence 2 grants they enable fast decisions but also cause predictable errors (balanced view). Sentence 3 lands the point: understanding how heuristics shape judgment can help design better decision-making environments. That last clause is the takeaway.
Step 2: Match. Option 3 \(--\) "understanding heuristics helps improve decision systems" \(--\) restates that final, purpose-stating sentence exactly.
Step 3: Eliminate. Option 1 ("eliminate heuristics") is too extreme; the passage never asks to remove them. Option 2 ("more harmful than useful") distorts the balanced tone \(--\) the passage credits their usefulness. Option 4 ("decisions cannot be improved") flatly contradicts the optimistic closing line.
Main idea: \( \text{Option 3} \)
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Approach Solution -2
Approach (component checklist): A correct main idea must contain both required parts of this passage's point, the subject (heuristics, cognitive shortcuts) and the claim (that understanding them helps build better decision systems). Score each option against these two components.
Option 1 keeps the subject but distorts the claim into “eliminate heuristics,” which the passage never asks for, fails the claim check. Option 2 keeps the subject but flips the claim into a purely negative verdict (“more harmful than useful”), contradicting the passage's balanced framing, fails the claim check. Option 4 drops the subject entirely and asserts something the passage never says (“decisions cannot be improved”), failing both checks and actually contradicting the passage's closing point. Option 3, “understanding heuristics helps improve decision systems,” keeps the subject intact and states the claim exactly as the passage's final sentence does, passes both checks.
Main idea: Option 3.
Option 1 keeps the subject but distorts the claim into “eliminate heuristics,” which the passage never asks for, fails the claim check. Option 2 keeps the subject but flips the claim into a purely negative verdict (“more harmful than useful”), contradicting the passage's balanced framing, fails the claim check. Option 4 drops the subject entirely and asserts something the passage never says (“decisions cannot be improved”), failing both checks and actually contradicting the passage's closing point. Option 3, “understanding heuristics helps improve decision systems,” keeps the subject intact and states the claim exactly as the passage's final sentence does, passes both checks.
Main idea: Option 3.
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Approach Solution -3
Concept:
Step 1: Build the idea chain.
Heuristics are useful because they allow quick decisions under uncertainty.
But they can also produce predictable errors.
Therefore, understanding their effect can help create better decision environments.
Step 2: Reject choices that break the balance.
Options 1 and 2 treat heuristics as purely harmful, which removes their stated benefit.
Option 4 says improvement is impossible, which contradicts the final sentence.
Step 3: Select the choice that keeps the conclusion.
Option 3 states that understanding heuristics helps improve decision systems. This preserves the therefore part of the passage without adding an extreme claim.
Final Answer: Understanding heuristics helps improve decision systems, option 3.
- Compress the passage into a because-but-therefore chain.
- The main idea must preserve both the usefulness and the risk of heuristics, then state why understanding them matters.
Step 1: Build the idea chain.
Heuristics are useful because they allow quick decisions under uncertainty.
But they can also produce predictable errors.
Therefore, understanding their effect can help create better decision environments.
Step 2: Reject choices that break the balance.
Options 1 and 2 treat heuristics as purely harmful, which removes their stated benefit.
Option 4 says improvement is impossible, which contradicts the final sentence.
Step 3: Select the choice that keeps the conclusion.
Option 3 states that understanding heuristics helps improve decision systems. This preserves the therefore part of the passage without adding an extreme claim.
Final Answer: Understanding heuristics helps improve decision systems, option 3.
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Top CAT Verbal Ability & Reading Comprehension (VARC) Questions
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The word ‘anarchy’ comes from the Greek anarkhia, meaning contrary to authority or without a ruler, and was used in a derogatory sense until 1840, when it was adopted by Pierre-Joseph Proudhon to describe his political and social ideology. Proudhon argued that organization without government was both possible and desirable. In the evolution of political ideas, anarchism can be seen as an ultimate projection of both liberalism and socialism, and the differing strands of anarchist thought can be related to their emphasis on one or the other of these.
Historically, anarchism arose not only as an explanation of the gulf between the rich and the poor in any community, and of the reason why the poor have been obliged to fight for their share of a common inheritance, but as a radical answer to the question ‘What went wrong?’ that followed the ultimate outcome of the French Revolution. It had ended not only with a reign of terror and the emergence of a newly rich ruling caste, but with a new adored emperor, Napoleon Bonaparte, strutting through his conquered territories.
The anarchists and their precursors were unique on the political Left in affirming that workers and peasants, grasping the chance that arose to bring an end to centuries of exploitation and tyranny, were inevitably betrayed by the new class of politicians, whose first priority was to re-establish a centralized state power. After every revolutionary uprising, usually won at a heavy cost for ordinary populations, the new rulers had no hesitation in applying violence and terror, a secret police, and a professional army to maintain their control.
For anarchists the state itself is the enemy, and they have applied the same interpretation to the outcome of every revolution of the 19th and 20th centuries. This is not merely because every state keeps a watchful and sometimes punitive eye on its dissidents, but because every state protects the privileges of the powerful.
The mainstream of anarchist propaganda for more than a century has been anarchistcommunism, which argues that property in land, natural resources, and the means of production should be held in mutual control by local communities, federating for innumerable joint purposes with other communes. It differs from state socialism in opposing the concept of any central authority. Some anarchists prefer to distinguish between anarchist-communism and collectivist anarchism in order to stress the obviously desirable freedom of an individual or family to possess the resources needed for living, while not implying the right to own the resources needed by others. . . .
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Among the connections between climate change and waste, O’Neill . . . highlights that “devices developed to reduce our carbon footprint, such as lithium batteries for hybrid and electric cars or solar panels[,] become potentially dangerous electronic waste at the end of their productive life.” The disposal of toxic waste has long perpetuated social injustice through the flows of waste to the Global South and to marginalized communities in the Global North . ..
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European translator of . . . Arabian Nights [which] started as a series of translations of an
incomplete manuscript of a medieval Arabic story collection. . . But, though those tales were of
medieval origin, Aladdin may be a more recent invention. Scholars have not found a manuscript of the story that predates the version published in 1712 by Galland, who wrote in his diary that he first heard the tale from a Syrian storyteller from Aleppo named Hanna Diyab . . .
Despite the fantastical elements of the story, scholars now think the main character may
actually be based on a real person’s real experiences. . . . Though Galland never credited Diyab in his published translations of the Arabian Nights stories, Diyab wrote something of his own: a travelogue penned in the mid-18th century. In it, he recalls telling Galland the story of Aladdin [and] describes his own hard-knocks upbringing and the way he marveled at the extravagance of Versailles. The descriptions he uses were very similar to the descriptions of the lavish palace that ended up in Galland’s version of the Aladdin story. [Therefore, author Paulo Lemos] Horta believes that “Aladdin might be the young Arab Maronite from Aleppo, marveling at the jewels and riches of Versailles.” . . .
For 300 years, scholars thought that the rags-to-riches story of Aladdin might have been
inspired by the plots of French fairy tales that came out around the same time, or that the story was invented in that 18th century period as a byproduct of French Orientalism, a fascination with stereotypical exotic Middle Eastern luxuries that was prevalent then. The idea that Diyab might have based it on his own life — the experiences of a Middle Eastern man encountering te French, not vice-versa — flips the script. [According to Horta,] “Diyab was ideally placed to embody the overlapping world of East and West, blending the storytelling traditions of his homeland with his youthful observations of the wonder of 18th-century France.” . . .
To the scholars who study the tale, its narrative drama isn’t the only reason storytellers keep
finding reason to return to Aladdin. It reflects not only “a history of the French and the Middle
East, but also [a story about] Middle Easterners coming to Paris and that speaks to our world
today,” as Horta puts it. “The day Diyab told the story of Aladdin to Galland, there were riots
due to food shortages during the winter and spring of 1708 to 1709, and Diyab was sensitive to those people in a way that Galland is not. When you read this diary, you see this solidarity
among the Arabs who were in Paris at the time. . . . There is little in the writings of Galland thatwould suggest that he was capable of developing a character like Aladdin with sympathy, but Diyab’s memoir reveals a narrator adept at capturing the distinctive psychology of a young protagonist, as well as recognizing the kinds of injustices and opportunities that can transform the path of any youthful adventurer.” - Contemporary internet shopping conjures a perfect storm of choice anxiety. Research has
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recommend the products and services that help achieve it. . . .
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Instead of making sense of a sea of existing stuff, these companies claim to disrupt stuff as
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things, and an ability to opt out of the stuff rat race. . . .
One-thousand-dollar mattresses and $300 suitcases might solve choice anxiety for a certain tier of consumer, but the companies that sell them, along with those that attempt to massage the larger stuff economy into something navigable, are still just working within a consumer market that’s broken in systemic ways. The presence of so much stuff in America might be more valuable if it were more evenly distributed, but stuff’s creators tend to focus their energy on those who already have plenty. As options have expanded for people with disposable income, the opportunity to buy even basic things such as fresh food or quality diapers has contracted for much of America’s lower classes.
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Most of this heat, the researchers note, probably doesn’t make it all the way through the plumage and back to the penguins’ bodies, but it could make a slight difference. At the very least, the method by which a penguin’s plumage wicks heat from the bitterly cold air that surrounds it helps to cancel out some of the heat that’s radiating from its interior. And given the Emperors’ unusually demanding breeding cycle, every bit of warmth counts. . . . Since [penguins trek as far as 75 miles to the coast to breed and male penguins] don’t eat anything during [the incubation period of 64 days], conserving calories by giving up as little heat as possible is absolutely crucial.
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