If you want to conclude that a given variable has a causal relation with a second variable, you have to be able to rule out other possible causal variables. The principle of causation involved here is the

Ruling out other possible causal variables rests on the internal validity rule of causation.

Internal validity secures the claim that the effect is due to the named cause and not confounds.

The temporal precedence rule requires the cause to occur before the effect, a different condition.

The covariance rule requires cause and effect to vary together, again a separate requirement.

Causal ambiguity is a problem to be avoided, not a principle establishing causation.

Covariation, time order and non-spuriousness together are the classic conditions for causal inference.