Logical Reasoning

PT109 · S1 · Q11 Researchers have discovered that caffeine

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Researchers have discovered that caffeine can be as physically addictive as other psychoactive substances.

Facts

Caffeine can be as physically addictive as any other psychoactive substance.

Some people have withdrawal symptoms from caffeine (depressed, drowsy, irritable).

As many people consume caffeine as consume any one of the other addictive psychoactive substances.

Evaluate

Not sure what to do with these facts. It doesn't seem like any of them chain together or give us conditional rules. It just sounds like caffeine is as addictive as other drugs, has some withdrawal symptoms, and is #1 or tied for #1 in popularity (number of users).

I wouldn't expect the middle sentence to be used in supporting the answer, both because Most Supported is famous for testing inferences that combine the first idea with the last idea, but also because that middle claim is so weakly worded (some = at least one person).

Goal

Look for something we can basically prove given only those three facts. Beware strong language. Expect that the comparative equalities (as addictive / used by as many people) will somehow come into play.

11.

Which one of the following can be logically concluded from the information above?

  1. There is no psychoactive substance

    Too Strong: #1 for addictions

    It says that caffeine can be as addictive, and it says that caffeine is tied for #1 or alone at #1 when it comes to number of people who consume it. But we don't have any info about the number of people addicted to caffeine, so we can't compare # of caffeine addicts to # of any other kind of addict.

    9% picked this

  2. A physical addiction to a

    Too Strong: typically

    We only know that caffeine, which is a psychoactive substance, sometimes give rise to diverse psychological withdrawal symptoms. This passage doesn't let us generalize that most addictions to psychoactive substances give rise to diverse psychological symptoms.

    11% picked this

  3. Not all substances to which

    Out of Scope: non-psychoactive

    Not all A's are B = Some A's are not-B, so this answer choice says, "at least one substance to which people can become physically addicted is not psychoactive". It would probably be tempting for people to say: "Right. Caffeine!" But caffeine is identified (twice) as a psychoactive substance, because it says "caffeine can be as addictive as any other psychoactive substance" in the first sentence and uses that same "any other" formulation in the last sentence too. When you say "X is just as funny as any other clown", you're implying that X is a clown.

    20% picked this

  4. If one is physically addicted

    Too Strong: conditional

    We only know that some people have "unusual depression" as a withdrawal symptom from caffeine. We can't take that fact and support a conditional rule that "if addicted to any psychoactive substance, then unusually depressed will be one your withdrawal symptoms."

    8% picked this

  5. Correct

    If alcohol is a physically

    Why this is right

    We know that "at least as many people consume caffeine as consume any other psychoactive substance". So if Rice Krispies is a psychoactive substance, then at least as many people consume caffeine as consume Rice Krispies. Because of that last sentence, we know that if alcohol is a psychoactive substance, then at least as many people consume caffeine as alcohol. If at least as many consume caffeine, then it's fair to say there are not more who consume alcohol.

    Skill tested: Must be True · how this choice captures the argument's function is the move to repeat next time.

    52% picked this

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