My argument is in outline as follows: that that absolute certitude which we were able to possess, whether as to the truths of natural theology, or as to the fact of a revelation, was the result of an assemblage of concurring and converging probabilities, and that, both according to the constitution of the human mind and the will of its Maker; that certitude was a habit of mind, that certainty was a quality of propositions; that probabilities which did not reach to logical certainty, might create a mental certitude; that the certitude thus created might equal in measure and strength the certitude which was created by the strictest scientific demonstration; and that to have such certitude might in given cases and to given individuals be a plain duty, though not to others in other circumstances:—(From Apologia Pro Vita Sua
Created in God's image and called to know and love him, the person who seeks God discovers certain ways of coming to know him. These are also called proofs for the existence of God, not in the sense of proofs in the natural sciences, but rather in the sense of "converging and convincing arguments", which allow us to attain certainty about the truth. These "ways" of approaching God from creation have a twofold point of departure: the physical world, and the human person.(from Catholic Catechism)
The same Holy Mother Church holds and teaches that God, the source and end of all thing can be known with certainty from the consideration of created things by the natural power of human reason : ever since the creation of the world, his invisible nature has been clearly perceived in the things that have been made. (from the Decrees of the First Vatican Council)
‘But I’m not an apostate’ I always add to my admission of heresy. I have always respected the Catholic Church's philosophic acuity and I find interesting the subtle divergence from the straightforward certainty as represented by the edict of the First Vatican Council and the Newmanian modulation of the Catechism. The curious thing is that those American philosopher Catholics who blog on this question seem to support the earlier position in a quite robust way. Perhaps the vertiginous abyss of fideism or irrationalism is a fear and the middle path between strict demonstration and pure fideism that Newman tried to strike is too narrow for minds blunted by the occupational hazard of rationalism.
((related posts: conversion