Argument Evaluation

Consider the following argument: Over the past decade, city statistics show a strong correlation between the number of ice cream cones sold and the number of shark attacks at local beaches. Clearly, eating ice cream makes a person more attractive to sharks.

The logical flaw in this argument is that it mistakes a necessary condition for a sufficient condition.

Nutritionist: The new energy bar, PowerBite, consists of 25% pure whey protein, whereas our current best-selling bar, MaxEnergy, consists of only 15% whey protein. Since whey protein is the primary driver of muscle recovery after strenuous workouts, athletes looking to maximize their muscle recovery should immediately switch from eating MaxEnergy bars to eating PowerBite bars.

Which of the following, if true, most seriously weakens the nutritionist's argument?

For each logical argument presented, identify the specific piece of additional evidence that provides the strongest logical support for its main conclusion.

Match each argument below to the piece of new evidence that most directly weakens its conclusion.

City Council Member: Last month, we installed a new, synchronized traffic light system at the Oak Street intersection. This month, the number of traffic accidents at that intersection dropped by 30% compared to the previous month. Therefore, the new traffic light system has clearly improved safety by reducing accidents at the Oak Street intersection.

Which of the following, if true, most seriously weakens the city council member's argument?

Factory Safety Director: Last year, 85 percent of the reported injuries at our manufacturing plant happened during the morning shift, whereas only 15 percent occurred during the evening shift. It is clear from this data that our morning shift operations are inherently more hazardous than our evening shift operations.

Which of the following most accurately describes a flaw in the Factory Safety Director's reasoning?

Linguist: Tarania's indigenous language features a complex tonal system, structurally identical to mainland languages 2,000 miles away, but unlike the non-tonal languages of neighboring islands. Anthropologists argue this tonal system evolved independently due to similar acoustic environments between Tarania and the mainland. However, geological records prove Tarania's environment has always resembled its non-tonal neighbors, not the mainland. Therefore, Tarania's tonal system must have been introduced by ancient mainland settlers who migrated to the island.

Which of the following, if true, most strongly supports the linguist's conclusion?

Historian: In the seventeenth-century town of Oakhaven, merchant records show a sudden surge in the importation of foreign spices immediately following a prolonged period of severe drought. Some scholars argue this indicates that the town's elite significantly increased their wealth during the drought. However, it is more likely that the drought destroyed local herb crops, forcing residents to rely heavily on imported spices for basic food preservation. Which one of the following, if true, most strengthens the historian's argument?

Argument: A recent study observed that individuals who consume green tea daily are significantly less likely to contract the common cold compared to those who do not drink green tea. The researchers concluded that specific antioxidants in green tea actively strengthen the immune system against cold viruses.

Statement: The new evidence that individuals who drink green tea daily are also much more likely to practice rigorous hand hygiene and avoid crowded places during cold season weakens the researchers' conclusion.

Linguist: To completely understand a newly discovered language, researchers must be able to accurately translate its idiomatic expressions. However, the idioms of any language are deeply rooted in the unique historical experiences of the culture that speaks it. Since the historical experiences of the recently contacted Zephyrian culture are entirely undocumented and inaccessible to outsiders, researchers will never be able to completely understand the Zephyrian language.

Evaluate whether the following statement is true or false:
The linguist's argument logically depends on the assumption that researchers cannot accurately translate a language's idiomatic expressions without having access to the unique historical experiences of the culture that speaks it.

Ornithologist: Ten years ago, our city implemented a 'Dark Sky' ordinance to reduce nighttime light pollution, which disorients migrating warblers and causes fatal building collisions. Since then, the population of warblers migrating through the city has continued to decline. Critics claim the ordinance failed to protect the birds. However, this is unwarranted. The continued decline is actually caused by the recent, rapid deforestation of the warblers' southern wintering grounds.

Which one of the following, if true, most helps to strengthen the ornithologist's argument?

Archaeologists recently discovered a high concentration of grinding stones at a 12,000-year-old settlement in the Zaran Valley, predating known agriculture in the region by 2,000 years. Residue analysis of these stones revealed trace amounts of wild cereal grains. Based on this, the lead researcher concluded that the valley's ancient inhabitants systematically processed and stored wild grains as a primary food source long before crop domestication. Which of the following statements, if true, would most strengthen the researcher's argument? Select all that apply.

Economist: To mitigate the economic stagnation caused by our aging workforce, the government recently introduced aggressive tax incentives for corporations that invest in automation technology. Proponents argue this will elevate overall industrial productivity. However, these incentives will actually exacerbate the current economic stagnation. To take advantage of these incentives, corporations will inevitably fund their automation investments by diverting capital away from employee training programs, which are currently the sole driver of productivity growth in our remaining workforce.

Which one of the following is an assumption on which the economist's argument depends?

Consider the following argument: 'Every time a new bakery opens in our neighborhood, crime rates drop slightly. Therefore, the smell of fresh bread must be deterring criminals.'

The reasoning in this argument is flawed because it relies on the testimony of an unreliable authority.

Agricultural Scientist: To combat devastating spongy moth infestations in commercial apple orchards, researchers developed a synthetic pheromone that completely masks the natural mating scent of female moths, preventing males from locating them. Although this pheromone degrades rapidly and requires costly weekly applications throughout the breeding season—unlike traditional broad-spectrum chemical pesticides which require only a single, inexpensive annual spray—orchard owners who transition exclusively to the synthetic pheromone will ultimately see higher profit margins.

Which of the following are assumptions on which the agricultural scientist's argument depends? (Select all that apply.)

Botanist: To survive in the hyper-arid Atacama Desert, the Copiapoa cactus relies exclusively on regular coastal fog for hydration. However, recent atmospheric warming has permanently shifted this fog condensation layer to significantly higher altitudes, completely bypassing the low-lying valleys where the native Copiapoa populations are rooted. Because these cacti cannot survive for more than a few months without moisture, the only way to prevent the extinction of the Copiapoa in the wild is to artificially relocate the remaining populations to these higher elevations.

Evaluate the following statement: The botanist's argument depends on the assumption that artificially relocating the remaining Copiapoa populations to higher elevations will successfully prevent their extinction in the wild.

Philosopher: A genuinely altruistic act requires that the agent act solely for the benefit of another, devoid of any subconscious or conscious anticipation of a personal payoff. Yet, neurological studies demonstrate that when humans assist others in distress, their brains consistently release neurotransmitters that induce a profound sense of psychological well-being. Because humans are neurologically conditioned to expect this internal sensation when performing charitable acts, we must conclude that humans are incapable of genuine altruism.

Which one of the following is an assumption on which the philosopher's argument depends?

Match each of the following arguments regarding a city transit authority's transition to electric buses (Left) with the newly discovered piece of evidence (Right) that most effectively strengthens its specific conclusion.

Marine Biologist: The recent severe decline in the local population of tufted puffins is driven by new commercial fishing operations off the coast. The puffin population started dropping sharply three years ago, precisely when these commercial fleets began large-scale harvesting of sand lance, the puffin's primary food source.

Statement: A cessation of the commercial harvesting of sand lance would result in a full recovery of the local tufted puffin population.

The statement above is a necessary assumption of the marine biologist's argument.

Anthropologist: Chemical analysis of obsidian blades found at the ancient inland Xoloti settlement perfectly matches the isotopic signature of the coastal Yuma quarry, located 400 miles away across the barren Sunu Desert. Clearly, the Xoloti must have engaged in direct, long-distance trade expeditions with the coastal Yuma people to obtain this material, rather than acquiring it gradually through a chain of intermediate, shorter trade networks involving other settlements.

Which of the following, if true, would most strengthen the anthropologist's argument? Select all that apply.