At a recent conference on "ethics and nuclear weapons" a moral theologian established succinctly and precisely, on the basis of Catholic teachings, that nuclear weapons are immoral. Though he granted that it is often necessary to do evil in order to do good, and though he alluded to the historic teaching. that, in the course of a just- war, it may be necessary incidentally to cause the death of innocent persons, he did not find in these rules sufficient justification for the use of major nuclear weapons;