If your friend seems happy only after her parents come for a visit, you assume the visits cause her happiness. You reach this conclusion by using the principle of

Question

Quizplus · Accepted Answer

The principle of covariation suggests that we attribute a cause to an effect when the cause is present whenever the effect occurs. In this case, your friend's happiness is attributed to her parents' visits because her happiness coincides with their presence.

If Your Friend Seems Happy Only After Her Parents Come