After a long struggle against liberal tendencies in the Church of England and an unsuccessful attempt to establish the position of Anglicanism as a branch of historical Christianity whose doctrines could be proven to be identical with those of the primitive Church, John Henry Newman came to the painful realization that he could no longer remain a member of the Anglican Church. Increasingly drawn to Catholicism, he was nevertheless repulsed by the idea that the Roman Church, while preserving many ancient doctrines, had contaminated the faith by mixing into it its own invented traditions. Or could it be that these "new" doctrines were truly already present from the beginning, having only become more explicit and better understood with the passage of the centuries? "So, I determined to write an essay on Doctrinal Development; and then, if, at the end of it, my convictions in favour of the Roman Church were not weaker, to make up my mind to seek admission into her fold" (Newman, Apologia Pro Vita Sua). - Summary by ekortright