Week 13 Quiz

Popper proposed falsifiability as a test for separating science from non-science: a scientific claim makes predictions that some possible observation could show to be false. Which illustrative claim is testable in that sense?

Select one.

• "This tea balances your energy, though no measurement of any kind, by anyone, could ever show the change."
• "Students who sleep eight hours before a quiz finish it faster, on average, than students who sleep four hours."
• "The energy bracelet boosts your energy, and no test can measure its effect."
• "This charm brings good luck in ways no one could ever notice or record."

A friend dismisses a well-supported idea in science by saying, "It's only a theory." In science, what does the word theory mean?

Select one.

• A hunch that scientists have not yet had time to test
• A proposed explanation that is still being tested and may soon be dropped
• A well-tested, broad explanation of many observations
• A claim that no possible observation could ever show to be wrong

An illustrative test of the hypothesis that a kitchen smoke alarm chirps because its battery is low. P1: If the battery is low, then a new battery will stop the chirping. P2: A new battery did not stop the chirping. C: The battery is not the cause. Which form does this reasoning take?

Select one.

• Modus tollens, a valid form
• Affirming the consequent, an invalid form
• Denying the antecedent, an invalid form
• Hypothetical syllogism, a valid form

In the same illustrative test, suppose the chirping stops instead. P1: If the battery is low, then a new battery will stop the chirping. P2: A new battery did stop the chirping. C: The battery was low. Which statement about this reasoning is accurate?

Select one.

• It is modus ponens, so the passed test proves beyond any doubt that the battery was low
• It is modus tollens, so the conclusion follows with certainty
• It denies the antecedent, so the battery could not have been low
• It affirms the consequent, so the passed test supports the hypothesis without proving it

An illustrative cold-supplement ad prints 12 customer testimonials. In a blinded trial, 120 adults with colds are randomly assigned, 60 to the supplement and 60 to a look-alike placebo. Within a week, 51 of 60 in each group feel better. What does the trial show?

Select one.

• The supplement works for 85 percent of adults, so the trial confirms all 12 of the testimonials
• 85 percent recovered in both groups, so the supplement did no better than the placebo
• 51 percent recovered in both groups, so most adults did not get better
• The 12 testimonials outweigh the trial, since each is a real recovery

An illustrative ad for an energy bracelet says no test can measure its effect, fills its page with customer stories, and claims that big labs want to hide the truth. That is 3 of the 5 warning signs of pseudoscience. What follows?

Select one.

• The signs are a strong reason to investigate, not a proof that the bracelet fails
• The signs prove the bracelet fails, since three of the five signs make up a clear majority of them
• The signs show nothing, since a claim no one can test cannot be judged at all
• The signs show the bracelet works, since no test has ever disproved it

An illustrative car will not start. Clues: the engine only clicks, the dashboard lights are dim, and the headlights were left on overnight; the fuel gauge reads half full. Rivals: a dead battery, an empty fuel tank, a failed starter motor. Which is the best explanation, and why?

Select one.

• An empty fuel tank, since a car with no fuel cannot start at all
• A failed starter, since the clicking is the most telling clue
• A dead battery, since it explains all three clues and fits the gauge
• None yet, since no explanation can be chosen until one of the rivals has been proven true

Which work gave inference to the best explanation, reasoning to the hypothesis that would best explain the evidence, its modern name?

Select one.

• Locke (1690), An Essay Concerning Human Understanding
• Mill (1843), A System of Logic
• Popper, The Logic of Scientific Discovery
• Harman (1965), "The Inference to the Best Explanation", The Philosophical Review

Which fallacy does this illustrative passage commit? "No one has ever proven that the old dorm is not haunted, so it must be haunted."

Select one.

• Appeal to ignorance (ad ignorantiam)
• Appeal to unqualified authority (ad verecundiam)
• Hasty generalization
• After this, therefore because of this (post hoc)

True or false: Hume's problem of induction shows that every inductive argument is as weak as every other, so a controlled trial gives no better reason to believe its conclusion than one anecdote does.

True or false.

• True
• False