Many of the answers here are pointing to methods, but I take this question as more fundamental. Epistemologically, causation is the intersection of three thing

Many of the answers here are pointing to methods, but I take this question as more fundamental. Epistemologically, causation is the intersection of three things: 1) Temporal precedence 2) Covariance (i.e. correlation) 3) Absence of likely alternative explanations Number 3 is by far the trickiest. Our inability to definitively rule out all possible alternatives means one has to resort to inference where causation is concerned.