Causality

Describes a causal relationship between two events or phenomena, i.e. that one is caused by the other.

The steeper angle of the sun’s rays in summer causes higher temperatures at that time of year.

It is important to distinguish the concept of causality from that of correlation, which refers to a common occurrence of the events or phenomena but does not imply a causal relationship.

As a general rule, when phenomena 𝚨 and 𝐁 occur in correlation (i.e. either simultaneously or consecutively), the following possibilities must be considered:

1. 𝚨 causes 𝐁 (direct causal relationship).
2. 𝐁 causes 𝚨 (reverse causal relationship).
3. A third event 𝐂 causes both 𝚨 and 𝐁 (external causal relationship).
4. 𝚨 causes other events: e.g. 𝐂, 𝐃, etc, which in turn cause 𝐁 (indirect causal relationship).
5. 𝚨 and 𝐁 are not causally connected, but only occur together by chance (spurious correlation).
6. 𝚨 and/or 𝐁 are observational errors and at least one of the phenomena does not occur at all in the form described (e.g. frequency illusion, base-rate fallacy, etc.)

The fact that 𝚨 and 𝐁 correlate with each other, i.e. that they regularly occur together, is not sufficient to postulate a causal relationship.

• Spurious correlation
• Causal illusion

• Causality on Wikipedia