Traditionally, doctrinal development was understood to be an authentic growth in the Church’s understanding and articulation of what had always been believed and taught. By examining the Church of antiquity and noting the doctrinal development within that antiquity, only then could one devise a theory on the nature of doctrinal development. The Need for an Infallible AuthorityHaving established the necessity of doctrinal development, Newman takes up the issue of how one is to discern authentic doctrinal development from false or unauthentic doctrinal development. Newman’s Seven Principles of Authentic Doctrinal DevelopmentTo judge the validity of a development, Newman compiled seven criteria or principles that must be present within all true doctrinal development. There is an inherent logic to this historical doctrinal development, though one that cannot be reduced to a syllogism.