Argument Evaluation

Medical Researcher: The experimental drug Lexicon has demonstrated a remarkable ability to neutralize the synthetic pathogen V-7 in laboratory settings. Based on this, several public health officials are lobbying for its immediate mass production. This enthusiasm is unwarranted. Historical data reveals that of all the experimental drugs that successfully neutralized synthetic pathogens in laboratories over the past twenty years, fewer than ten percent were ultimately approved as safe for public consumption. Consequently, there is a greater than ninety percent probability that Lexicon will fail to neutralize V-7 in human patients.

The reasoning in the medical researcher's argument is most vulnerable to criticism on the grounds that the argument does which one of the following?

Match each flawed or incomplete argument regarding the restoration of the Fresco of Verano to the sufficient assumption that, if true, logically guarantees its conclusion.

Read the following argument:

Any synthetic chemical compound that bonds effectively with the Z-receptor will inhibit the replication of the delta-virus. The newly synthesized compound, Brivanex, was designed specifically to target the Z-receptor. Therefore, Brivanex will successfully cure patients infected with the delta-virus.

Is the following statement true or false?

The assumption 'Any compound that inhibits the replication of the delta-virus will successfully cure patients infected with it' is sufficient to logically guarantee the argument's conclusion.

Consider the following argument:

A terrestrial organism can survive prolonged exposure to atmospheric argon only if its cellular membranes contain cryptobiotic proteins. The newly discovered deep-cave lichen *Verrucaria argonensis* contains cryptobiotic proteins in its cellular membranes. Thus, *Verrucaria argonensis* can survive prolonged exposure to atmospheric argon.

The assumption "No terrestrial organism's cellular membranes contain cryptobiotic proteins unless that organism can survive prolonged exposure to atmospheric argon" logically guarantees the argument's conclusion.

Match each of the following brief arguments to the abstract description that most accurately identifies its logical flaw.

Biologist: A localized ecosystem can successfully recover from the abrupt loss of its apex predator only if the population of its primary consumers is actively restricted and the habitat's foundational flora remains largely intact. In the Veridian Valley ecosystem, a viral pathogen recently eradicated the native cougar population, which served as the sole apex predator. Although state wildlife officials have implemented an aggressive culling program that is successfully restricting the population of primary consumers, the Veridian Valley ecosystem will nevertheless fail to recover from the loss of the cougars.

Which one of the following, if assumed, enables the biologist's conclusion to be properly drawn?

Below are four distinct arguments, each relying on an unstated bridging rule. Pair each specific argument with the general principle that, if valid, would logically guarantee the argument's conclusion.

Match each flawed argument stimulus to the abstract description that most accurately identifies its logical error.

Sociologist: Sustaining rapid economic growth requires a society to foster a culture of widespread technological innovation. However, a society will fail to cultivate such a culture if it does not possess a robust and accessible educational system. Observers note that several developing nations are currently investing heavily to overhaul and expand their educational infrastructure. Therefore, it is inevitable that these nations will soon experience sustained rapid economic growth.

Which of the following most accurately describes a flaw in the sociologist's reasoning?

Read the following argument and evaluate the statement below it.

Archaeologist: Historical records show that whenever an ancient empire rapidly expanded its territory, it subsequently suffered a severe economic depression due to overextended supply lines. Recent analysis of the ancient Valerian Empire reveals that it suffered a catastrophic economic depression in its final decades. Therefore, the Valerian Empire must have rapidly expanded its territory shortly before its fall.

Statement: The archaeologist's argument is vulnerable to criticism because it draws a broad conclusion about ancient empires based on a single, potentially unrepresentative historical example.

Researcher: The hormone somatotropin stimulates growth in juvenile *Rana clamitans*. In a strictly controlled laboratory study, two groups of these frogs were observed for six months. Both groups were provided with identical diets and environmental conditions, differing only in the water's dissolved calcium concentration. The frogs in the high-calcium water exhibited growth rates 30 percent higher than those in the low-calcium water. Because both groups of frogs synthesized identical amounts of somatotropin over the study period, the dissolved calcium must directly enhance the sensitivity of the frogs' cellular growth receptors to this hormone.

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

Epidemiologist: Proponents of the new hospital sanitation directive claim that it significantly reduces the rate of nosocomial (hospital-acquired) infections. They support this by pointing out that in the two years since the directive was issued at General Hospital, the number of nursing staff fully complying with the directive has steadily risen, which has in turn fostered a culture of heightened hygiene awareness. But the proponents' claim is entirely misguided. Over that exact same two-year period, the overall rate of nosocomial infections at General Hospital actually increased by 12 percent.

The epidemiologist's argument is most vulnerable to criticism on the grounds that it...

Match each flawed argument (which lacks a necessary premise to be logically valid) with the sufficient assumption that, if added to the premises, would allow its conclusion to be properly drawn.

Below are four distinct arguments that rely on unstated conditional rules. Pair each argument with the corresponding overarching principle that conclusively bridges the gap between its premises and its conclusion.

Cardiologist: In a recent clinical trial, patients with mild hypertension who took a daily dose of compound X experienced a 10 percent greater reduction in blood pressure than patients who received a placebo. Compound X has virtually no side effects, whereas conventional blood pressure medications often cause persistent fatigue and dizziness. Therefore, to minimize patient discomfort while effectively managing their condition, doctors should prescribe compound X instead of conventional medications for patients with mild hypertension.

Which of the following would be most useful to know in order to evaluate the cardiologist's argument?

Match each of the following argumentative scenarios with the universal principle that, if assumed to be valid, most strongly justifies its conclusion.

Match each flawed argument stimulus to the abstract description of the logical error it commits.

Read the following argument, then evaluate the statement below it.

Political Commentator: In any robust democracy, the ruling party will inevitably face plummeting approval ratings during an economic recession. The ruling Coalition Party is currently facing plummeting approval ratings amidst a severe economic recession. Therefore, despite recent claims to the contrary by international observers, it is clear that our country remains a robust democracy.

Statement: The commentator's reasoning is flawed because it infers that a certain political condition is absent merely on the grounds that a condition sufficient to guarantee its presence is absent.

Consider the following argument:

Public Health Official: Last year, the city launched a comprehensive campaign to encourage drivers to wear seatbelts. The campaign drastically changed behavior: surveys confirm that the proportion of drivers in the city who regularly wear seatbelts surged from 40 percent last year to 80 percent this year. However, recent traffic reports reveal that the total number of severe injuries resulting from car accidents in the city has actually increased by 15 percent compared to last year. Clearly, wearing a seatbelt does not actually reduce a driver's risk of suffering a severe injury in a car accident.

Statement: The official's argument is actively weakened by the new finding that the total number of car accidents in the city also increased by exactly 15 percent over the past year.

Marine biologist: In a decisive effort to protect the endangered crested sea turtle, the regional government has recently enacted a comprehensive ban on all commercial net fishing within the Emerald Gulf. This legislative action was primarily justified by extensive ecological studies demonstrating that adult crested sea turtles frequently become fatally entangled in these commercial nets during their migratory patterns. Therefore, by eliminating this specific environmental hazard, the new ban will likely cause the overall crested sea turtle population to increase significantly over the course of the next decade.

Statement: Determining whether the commercial net fishing operations in the Emerald Gulf had been significantly depleting populations of predatory fish that feed heavily on crested sea turtle hatchlings is critical to evaluating the validity of the marine biologist's argument.