Logical reasoning PrepTest 125 · Section 2 · Question 15

Incorrect. The argument defines rationality, and then it highlights two situations where that capacity isn't demonstrated. While there is a shift from a definition about capacity to an argument that relies on two examples being enough to show a group isn't rational, that's a matter of scope, not definition.

Incorrect. Awareness of one's own behavior isn't established as part of the definition of rationality, so this answer is out of scope.

Incorrect. First, the author of this argument might very well believe that animals are more rational than humans—the conclusion just states it'd be absurd to view humans as more rational. Second, even if we read the conclusion to mean that humans and animals are equally irrational, they don't have to make the same irrational acts to lead to that conclusion. Animals could have their own set of irrational behaviors allowing the conclusion to be drawn.

Incorrect. The argument is, essentially, that humans are no better than other animals—that leaves open the possibility that they're worse. The argument therefore doesn't assume this answer.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
Opposing point - Humans are rational and thus better than other animals
Rationality - Capacity for well-considered thinking/action
Humans - Pollute the Earth and deplete farming soil
Conclusion - Humans aren't rational (and aren't better than other animals)

Answer Anticipation:
There are two key elements in this stimulus that we can look at to find the flaw in the argument.

First, the argument compares humans and animals. The opposing point says that humans are better than animals because of a capacity for rational thought, whereas the argument concludes that it's "absurd" to think humans are better than animals. Even if we accept humans aren't rational (we'll come back to that in a second), this is still an incomplete comparison. It's possible that there are other reasons to believe that humans are superior to animals, and so this argument is flawed in failing to consider those.

Second, the argument has a very strong conclusion—humans are "not rational." There's no wiggle room there! Are the premises strong enough to support that conclusion? Not at all. While the argument does highlight two situations where humans don't act rationally, that's not enough to show they're not rational. There may be other situations where humans do display rationality. Also, "rational" is defined as having the capacity for well-considered thought/action, not that one always acts in such a manner.

Either of these flaws could show up in the correct answer, so let's keep our eyes open for both.

Answer Explanation:
This answer highlights the difference between the definition of rationality—having the capacity to take well-considered actions—and the means by which the argument attempts to establish that humans aren't rational. While humans may act irrationally in the way they treat the environment, that doesn't mean they don't have the capacity for rational thought and just aren't displaying it in this area.

Key Takeaway:
Always be aware of how strong the conclusion is. The stronger the language, the stronger the premises needed to validly support it. If the conclusion is absolutely strong, make sure the premises are, too.