What it is
Correlation means two variables change together.
Causation means one variable directly causes the other.
These are not the same thing.
How it works
Two things can appear linked because of:
- A hidden third variable
- Coincidence
- External environmental factors
Without testing, we cannot assume cause-and-effect relationships.
Why it matters
Confusing correlation with causation leads to:
- Incorrect conclusions in research
- Misleading media headlines
- Flawed decision-making in policy and health
It is one of the most common reasoning errors in data interpretation.
Analogy
Ice cream sales and drowning rates both increase in summer.
But ice cream does not cause drowning.
Heat increases both swimming activity and ice cream consumption.
The real cause is temperature.



