> Part of the reason is that you need a-priori knowledge of the causal relationships (coarse grained I.e direction) between your variables. Isn't there a whole

> Part of the reason is that you need a-priori knowledge of the causal relationships (coarse grained I.e direction) between your variables. Isn't there a whole book, titled Causality by Dr. Pearl, on teasing causal relationships out of data, explicitly for this purpose?