  But the apparent usefulness of a “principle of universal causality” in accounting for a range of problems in qualitative common sense reasoning will be tantalizing to philosophers. And the causal theory, as initiated by Geffner and developed by Turner, has many interesting detailed features. For instance, while philosophical work on causality has concentrated on the causal relation, this work in logical AI shows that a great deal can be done by using only a nonrelational causal predicate.