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Lesson 6 of 10

The honest report

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7 min

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The forecast said sunny. It rained.

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Compare the prediction with what we see.
Step 1 of 3
  1. Compare the prediction with what we see.
  2. They match: confidence grows.
  3. They differ: re-check the ideas and the measurements.

The idea

Good laws and models let us predict new situations. Sometimes we can predict before we can do the experiment.

When a prediction matches what we see, we trust the science more. When it does not, scientists look at three things again. They check their assumptions. They check their model. They check their measurements. An assumption is something we take as true without testing.

A failed prediction does not show weak science. It points to what to explore next.

Even good theories have limits. A theory may fail in new conditions. It may fail when measurements get more precise. Scientists change an idea because of evidence, not opinion.

Weather forecasts show these limits. Wind, heat, damp air and air pressure all affect the weather. A tiny error at the start can grow with time. So a forecast for tomorrow is usually good. A forecast for next month is weak.

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