> I am going to have to protest your misrepresentation of statistics > in your most recent posting on this thread. Your mistake is a common one, > and must be stamped out repeatedly and vigilantly by statististicians. > > Your concept of "causal distance" is well and good for philosophical > discussion, provided you can define it with sufficient clarity. However, > statistics, no matter how exact, can only prove correlation, never > causation. Never said it could. Your claim of error can only be upheld by assuming that every reference to 'relationship' in my original post implied a reference to 'causal relationship'. I claimed that statistical analysis could establish a relationship between two events. So it can, such a relationship being called a correlation. > As to how correlation is linked to causation, the best answer is > weakly. Notice that correlation is symmetric, C(X, Y) = C(Y, X), > and yet one of the fundamental components of the concept of causality > is a lack of symmetry. (Few would argue that cancer causes smoking). Time flies like an arrow. > It is an all too common occurence in todays quantitative society > that statistics are called upon as evidence of causation. The > mantra that should be remembered is: 'Correlation not causation'. Are you saying that statistics CAN'T be used 'as evidence of causation', or only that this happens too OFTEN? I have no argument with statistics being unable to PROVE causation, but I would maintain that statistics can provide EVIDENCE towards a proof of causation (which underlies my contention that doubt about causation can be satisfied by a convincing statistical argument). ___Bob