Summary of The Half-Life of Facts

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The Half-Life of Facts book summary
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For decades, doctors and athletes appeared in print ads vouching for cigarettes. As a result, many people came to believe that smoking was beneficial. Now, everyone understands its dangers. That’s how fleeting knowledge can be. In this fascinating explanation of how “facts” come and go, mathematician Samuel Arbesman details why much of what people know to be true today will turn out to be false tomorrow. He offers thought-provoking ideas, theories and scientific findings to explain the impact of his main point: facts have a dwindling lifespan. getAbstract recommends his rundown on why information expires to people who want to be in the know – even when what they know tonight may be wrong by morning.

About the Author

Applied mathematician and network scientist Samuel Arbesman was a senior scholar at the Ewing Marion Kauffman Foundation. Currently, Arbesman is a senior adjunct fellow of the Silicon Flatirons Center for Law, Technology and Entrepreneurship at the University of Colorado, and an associate of the Institute for Quantitative Social Science at Harvard University.



True Today, False Tomorrow

People used to believe that the more meat you ate, the healthier you would become. Later, they believed that meat was bad for you; later still, they again believed that meat was good for you; now it’s all a matter of conjecture. The debate over red wine’s health benefits or detriments continues to the point of utter confusion. Everyone used to believe that all the stars in the universe – including the sun – orbited the Earth.

All of this proves one unshakeable truth: Knowledge is mutable. Like a radioactive substance, every known “fact” has a half-life. Scientists can “measure the amount of time” it takes “for half of a subject’s knowledge to be overturned.” They can determine the rate at which new facts develop, how fast they spread and how often they change. Facts – your “individual states of knowledge awareness” – fall into three categories:

  1. “Fast-changing facts” – These data are always in flux, like the weather report.
  2. “Slow-changing facts” – Some facts shift over great time spans, like the “number of continents” on Earth.
  3. “Mesofacts” – Certain facts change...

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