The key difference lies in what each one does: a scientific law describes what nature does under specific conditions, while a scientific theory explains how nature works.
Understanding Laws
A scientific law is a statement based on repeated experimental observations that describes some aspect of the universe. These laws often take the form of a mathematical equation. They predict results under certain conditions.
- What it does: Describes observed phenomena.
- Focus: Predicting what will happen.
- Example: Newton's Law of Universal Gravitation describes the attraction between objects with mass and allows us to predict their movements.
Understanding Theories
A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Theories provide the why behind observed phenomena.
- What it does: Explains observed phenomena.
- Focus: Explaining how something happens.
- Example: The Theory of Evolution explains the diversity of life on Earth through the process of natural selection.
Law vs. Theory: A Table for Comparison
| Feature | Scientific Law | Scientific Theory |
|---|---|---|
| Purpose | Describes what happens | Explains how something happens |
| Based on | Repeated observations and experimental evidence | Extensive evidence, incorporating facts and laws |
| Predictive Power | Predicts outcomes under specific conditions | Offers explanations and insights into underlying mechanisms |
| Example | Law of Conservation of Energy | Theory of General Relativity |
In essence, as the provided reference states, a law describes what nature does under certain conditions, and will predict what will happen as long as those conditions are met. Conversely, a theory explains how nature works.
