Overview
This lecture introduces the scientific hypothesis and prediction, clarifying their differences, relationships, and importance for experimental science reasoning and testing.
Scientific Hypothesis vs. Prediction
- A hypothesis is a potential explanation for an observation or phenomenon ("why" something happens).
- A prediction states what will happen in the future, often as a result of an experiment, but does not explain why.
- A hypothesis implies one or more predictions; if the hypothesis is true, its predictions must be true.
- If a prediction is false, the hypothesis it derives from is also false.
- A prediction being true does not guarantee the hypothesis is true, since multiple hypotheses can make the same prediction.
Testing Hypotheses and Predictions
- A scientific hypothesis must be testable—it must make at least one prediction that could prove it wrong (falsifiable).
- Hypotheses often involve mechanisms or unobservable factors and cannot be directly tested in a single observation.
- Hypotheses are tested indirectly by testing their predictions; predictions are tested directly through measurement.
- Disconfirming a prediction can falsify a hypothesis, while confirming a prediction can only show consistency, not proof.
Example: Acid Rain and Fish Deaths
- Observation: Fish are dying in a lake.
- Hypothesis: Acid rain from industrial air pollution is causing the deaths.
- Prediction: The lake water will be acidic.
- Testing: Measure the lake's pH; neutral pH would falsify the hypothesis.
- True prediction does not confirm the hypothesis, since other factors could cause acidic water.
Summary Table (Conceptual Points)
- Hypothesis: explanatory, primary, tested indirectly, can only be falsified.
- Prediction: non-explanatory, secondary, tested directly, can be true or false.
Key Terms & Definitions
- Hypothesis — A potential, testable explanation for an observation or phenomenon.
- Prediction — A specific statement about what will happen if the hypothesis is accurate.
- Falsifiable — Capable of being proven false by an observation or experiment.
Action Items / Next Steps
- Review the relationships and differences between hypotheses and predictions.
- Be prepared to apply these concepts in experimental design and scientific reasoning.
- Watch upcoming videos for more on mechanisms and hypothesis testing.