Logical Reasoning

PT108 · S3 · Q4 The average 40-year-old North American

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The average 40-year-old North American will have watched more than one million TV commercials in his or her lifetime.

Conclusion (we may conclude, therefore)

The TV commercial has influenced North American habits of thought.

Evidence

The average 40 year old North American will have watched more than one million TV commercials in his or her life.

Evaluate

Wow, that premise seems like an awfully high number. One million? Okay, okay, not our concern. We're accepting that average 40 year olds have seen a million commercials. People older than that have presumably seen more than a million (on average) and people younger somewhere under a million.

How do we leap to "it's influenced North American habits of thought"? Since our Conclusion has this brand new term, "habits of thought", which the answer choice needs to allow us to logically derive, the correct answer has to say "habits of thought" or something equivalent.

Goal

We can anticipate a basic, "If Premise, Then Conclusion" missing link. We have two facts about North Americans that need to be connected:

average 40 year old has → ads have influenced watched 1 million ads habits of thought

It's harder to predict what the trigger wording will say, but we need an answer that definitely applies to North America and delivers us the idea that "habits of thought have been influenced".

4.

The conclusion above follows logically if which one of the following is assumed?

  1. The habits of thought that

    Strengthens, Doesn't Prove

    Given that TV ads are an external influence and we're trying to prove that TV ads have influenced habits of thought, it strengthens to hear that habits of thought are largely determined by external influences. But this answer doesn't prove that one specific external influences, namely TV commercials, have influenced the habits of thought of North Americans.

    5% picked this

  2. Correct

    Anything people are exposed to

    Why this is right

    This has that lovably strong, absolute language we want in Sufficient Assumption, since our goal is to guarantee the conclusion. This is also a conditional rule that has the conclusion on the right side of the arrow, where we want it: if people have been exposed then X will to X in great quantity → influence their habits of thought Does this rule apply to North Americans and commercials? Have North Americans been exposed to TV commercials in great quantity? Sure, I mean the average 40 year old has seen 1 million. So then according to this rule, TV commercials will influence the average 40 year old's habits of thought. Thus we've proven that the TV commercial has influenced some North American habits of thought.

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

    80% picked this

  3. It is impossible to avoid

    Unrelated to Goal

    If the answer doesn't say "habits of thought" or a meaning match for that, it's functionally useless to us. The correct answer + the existing evidence must allow us to logically derive the conclusion. We can't derive "habits of thought" unless it appears in the correct answer or in the existing premises. It didn't appear in the premises, so it must appear in the correct answer.

    2% picked this

  4. Some people find television commercials

    Unrelated to Goal

    If the answer doesn't say "habits of thought" or a meaning match for that (i.e. "tendencies of thinking"), it's functionally useless to us. The correct answer + the existing evidence must allow us to logically derive the conclusion. We can't derive "habits of thought" unless it appears in the correct answer or in the existing premises. It didn't appear in the premises, so it must appear in the correct answer.

    0% picked this

  5. Certain forms of communication to

    Strengthens, Doesn't Prove

    Just like (A), given that TV ads are form of communication to which people are subjected, and given that we're trying to prove that TV ads have influenced habits of thought, it strengthens to hear that habits of thought can be affected by certain forms of communication people are subjected to. But this answer doesn't prove that one specific external influences, namely TV commercials, have influenced the habits of thought of North Americans. Sufficient Assumption is asking for us to 100% guarantee the conclusion, not just make it somewhat more likely to be true.

    12% picked this

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