>> Mathematics has not developed the asymmetric language required to capture our understanding that if X causes Y that does not mean that Y causes X.<p>There we go again. These assertions by Pearl discredit him. Yes, mathematics can capture this perfectly well, it's the implication relation in a nutshell: X → Y means that X causes Y but we don't know whether Y causes X.<p>I guess, strictly speaking, implication doesn't say anything specific about causality, so you could conceivably claim that A → B ("If A, then B") is not a causal relation, because even when B always follows A we can't be assured that A is the cause of B (e.g. two alarms might go off one after the other always), but that is really splitting hairs. The semantics of implication are broad enough that they can cover both strict causality relations _and many more besides_. The intended meaning can always be made explicit in language where it's not clear from the context ...and that's what Pearl is most likely complaining about. He basically wants a stricter interpretation that can only cover causal relations so that the meaning doesn't depend on the context. Because!<p>The whole point here is that Pearl wants his causal reasoning framework to be accepted by everyone, even if it's not really offereing anything radically new.