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Mental Models

Half Truths Are Not Whole Truths

Be wary of partial truths presented in persuasive messages, as they can be more dangerous than outright lies by omitting context and selecting favorable evidence.

THE IDEA

Whether it's Shell, AT&T, Facebook, or the Chinese government, the goal is the same. To persuade you when your guard is down. They know, and you know, that if the message were plastered with the word "ad" in big red letters, you'd ignore it. We would be remiss, however, if we didn't acknowledge that just because something's an ad doesn't mean it is false. Big companies are wary of ads backfiring. They fear the consequences of being outed as liars. But there are many forms of persuasion besides outright lying. An ad can tell only part of the story. It can leave out the broader context. It can ignore evidence that goes against the story the company wants to tell. It can emphasize some facts and de-emphasize others. It can use examples that tug at our heartstrings, even when those examples misrepresent general trends. A partial truth is often more dangerous and less easy to detect than a pack of lies. So, before fixating on the results of a new study, make sure you understand the broader context, that you have read the room, and that you resist the glow of the shiny new object until you've scoped out the territory and gotten the lay of the land.

When to use it

  • Evaluating advertisements and marketing claims

  • Analyzing political campaign messages and speeches

  • Assessing research studies presented in the media for cherry-picked data

  • Understanding corporate communications that may omit negative information

FROM THEORY TO EVERYDAY LIFE

In practice

01

Selective advertising

In a hypothetical example, a company's ad highlights that their product is recommended by 4 out of 5 dentists, but fails to mention that the survey was conducted only among dentists who received free samples.

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A MOMENT TO REFLECT

Put it to work.

  1. When you encounter a persuasive message, what questions can you ask to uncover missing context?

  2. Can you recall a time when a partial truth influenced your decision? How did you later discover the full story?

  3. How can you distinguish between a harmless omission and a manipulative half-truth?

CONTINUE THE CONVERSATION

Source texts

  • Verified How to Think Straight, Get Duped Less, and Make Better Decisions about What to Believe Online (Mike Caulfield, Sam Wineburg)
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