The idea that Roman Catholic doctrines for which there is no early testimony can be explained as logical deductions from undoubtedly early teachings is usually dismissed as obviously false. By invoking the logical properties of doctrines expressed as explicit generalizations, however, and by distinguishing deductions in which all the assumptions represent Apostolic doctrine from those in which all the doctrinal assumptions are Apostolic, a way is found to deduce the disputed doctrines while leaving the immutability of doctrine intact. Although a (...) theory of theological development is thus not needed to justify doctrinal additions, developments in theology nevertheless often motivate the authoritative pronouncements cited by doctrinal deductions. Finally, it is argued that a correct understanding of such deductions improves the prospects for reunion between those whose doctrinal axioms coincide even if differing historical information has rendered them incapable of following the same chain of deductions. (shrink)

Russell alleged that the version of the cosmological argument he debated with Copleston involved type confusions, but the definitions of plural descriptive functions and the ancestral in Principia Mathematica can be used to reformulate the argument in a type-safe way via a notion of causally self-sufficient classes. Although the argument depends on the assumption that the class of contingent things is not causally self-sufficient, if that assumption is weakened to say only that it may not be so, then a new (...) modalized version emerges which has similarities with recent ontological arguments but weaker and more intuitive assumptions. (Familiarity with Principia notation and conventions is presupposed throughout.). (shrink)