In the aftermath of the Irish referendum, the question has become: how could so many Catholics vote “yes” believing this would not undermine marriage? I suggest there is a reason that extends beyond Ireland, and extends to other ethical teachings. It has to do with a side-effect of scientific thinking.Scientific thinking focuses so predominantly on efficient causality (how change is brought about) that final causality (the end or purpose for which something is designed) gets lost to sight in people’s thinking. Things tend to mean whatever we make them mean by what we do with them (efficient causality); inherent meaning (final causality) no longer matters much.Leading up to this same law change in New Zealand, many people, in all good faith, could not see why the change w