7.4: Telling the Truth, While Still Misleading

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Page ID: 21995

Bradley H. Dowden
California State University Sacramento

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Even when you get all the relevant facts, there can be serious problems. It depends on how the facts are presented. Consider Grandpa's Granola Bars—pressed bars of breakfast cereal. The primary ingredient in Grandpa's Granola Bars is sugar. The manufacturer of this "health food bar" does not want to broadcast this fact, yet the manufacturer must obey federal law and list the ingredients in the order of their weight. (The U.S. Food and Drug Administration requires the main ingredient to be listed first.) The corporate management that is pushing Grandpa's Granola Bars has found a clever way to tell the sugar story: List each of the seven kinds of sugar separately. In this case, at the top of the list goes "rolled oats," followed by "sucrose, dextrose, fructose, honey, chocolate chips, invert sugar, and corn syrup." Clever of the manufacturer, but deceitful. The unwary reader might conclude, "Ah, the bar is mostly rolled oats." It is mostly sugar.

Exercise $\PageIndex{1}$

Analyze the following offer to determine whether you should join. This ad exploits people whose minds fog over when they see numbers.

BINGO! We’ve finally uncovered the secret, and we will share it with you for a small part of your profits. Here's how to claim your winnings from Las Vegas. The entry fee is only $19.95. The secret is that you play as a group. We arrange for you to play with 99 other players. That way, you can buy so many more bingo cards, and your chances of winning go up astronomically. In fact, we guarantee that your group will win at least $1,000, or double your money back. Act now. Send your entry fee to Dr. Dardanelles, 3381 Magdalen Ave., New York, NY 10009. Add $2 for our expenses.

This guy is going to give your group $1,000. Guaranteed! How could any logical reasoner walk away from such a good deal?

Answer

Analyze the following offer to determine whether you should join. This ad exploits people whose minds fog over when they see numbers.

This guy is going to give your group $1,000. Guaranteed! How could any logical reasoner walk away from such a good deal?