When you have contrived to persuade him that, for Catholics, the authority of the Church in matters of faith is not a self-evident axiom, but a truth arrived at by a process of argument, the Protestant controversialist has his retort ready. "You admit, then, after all," he says, "that a man has to use his own private judgment in order to arrive at religious truth? Why, then, what is the use of authority in religion at all? I had always supposed that there was a straight issue between us, you supporting authority and I private judgment; I had always supposed that you criticised me for my presumption in searching for God by the light of my imperfect human reason; it proves, now, that you are no less guilty of such presumption than myself! Surely your reproaches are inconsistent, and your distinctions unnecessary. If you use your private judgment to establish certain cardinal points of theology, the existence of God, the authority of Christ, and so on, why may not I use my private judgment to establish not only these, but all other points of theology--questions such as the doctrine of the Blessed Trinity, or the Real Presence in the Eucharist? You can hardly blame me for using the very privileges which you have just claimed so eagerly for yourself."

I could not have imagined, if I had not heard it with my own ears, the accent of surprise with which Protestants suddenly light upon this startling discovery, that the belief we Catholics have in authority is based upon an act of private judgment. How on earth could they ever suppose we taught otherwise? I say nothing here of the grace of faith, which is the hidden work of God in our souls. But how could the conscious process by which we arrive at any form of the truth begin without an act of private judgment? I may, indeed, overcome by a kind of emotional crisis, surrender myself unreflectively to an influence imaginatively experienced; but that is not Catholicism, it is Protestantism; it is "conversion" in its crudest form. If I employ my reason at all; if I employ my reason only so far as to say "The Church says this, and the Church is infallible, therefore this must be true," even so I am using private judgment; it is my own reason which draws its conclusions from the syllogism. Reject private judgment? Of course Catholics have never rejected private judgment; they only profess to delimit the spheres in which private judgment and authority have their respective parts to play.

Is it really so difficult to see that a revealed religion demands, from its very nature, a place for private judgment and a place for authority? A place for private judgment, in determining that the revelation itself comes from God, in discovering the Medium through which that revelation comes to us, and the rule of faith by which we are enabled to determine what is, and what is not, revealed. A place for authority to step in, when these preliminary investigations are over, and say "Now, be careful, for you are out of your depth here. How many Persons subsist in the Unity of the Divine Nature, what value and what power underlies the mystery of sacramental worship, how Divine Grace acts upon the human will--these and a hundred other questions are questions which your human reason cannot investigate for itself, and upon which it can pronounce no sentence, since it moves in the natural not in the supernatural order. At this point, then, you must begin to believe by hearsay; from this point onwards you must ask, not to be convinced, but to be taught." Is it really so illogical in us, to fix the point at which our private judgment is no longer of any service? Are we really more inconsistent than the bather who steps out cautiously through the shallow water and then, when it is breast-high, spreads out his hands to swim?

But there is a subtle and a more telling variation of the same argument. The strength of a chain, we are reminded is that of its weakest link. We Catholics profess to establish the truths of religion by a chain of argument; this chain, then, is no stronger than the weakest link in it. How is it that we profess to hold with absolute certitude the revealed truths of our religion? Reasonable enough to say that if your Church is infallible, the doctrines which she preaches are evidently true, and capable of producing absolute certitude in the mind. But the infallibility of your Church is not a self-evident axiom; it is a proposition which you have proved, and proved it by an appeal to ordinary human reason. Is it not clear, then, that in the last resort every statement which your Church makes rests upon the validity of the arguments by which, in the first instance, you proved your Church infallible? Now, these arguments, based as they are upon human reason, do not convey absolute certitude to the mind; they may be, in your view, overwhelmingly probable; nay, they may be certain with all human certainty; but human certainty is not absolute certainty. There is always a possible margin of error. You cannot prove the existence of God, the authority of Christ, or his commission to his Church, beyond all possibility of doubt; how then can you suppose that you have proved beyond all possibility of doubt the statements which you receive on the Church's authority?

To escape this dilemma, Catholic apologists have frequently used a metaphor which seems to me, I confess, singularly unfortunate. They tell us that the motives of credibility by which we establish the Divine origin of the Church, and her teaching office, are like the scaffolding which is put up while a building is being erected; once the building operations are complete, the scaffolding is unnecessary; it has served its turn, and we pay it no further attention. Now, theologically speaking, that metaphor will pass well enough; they mean that the true motive of our belief, seen on its supernatural side, is the infallible veracity of God in his revelation. But for purposes of apologetic, we shall employ such a metaphor in vain. Our critics will not be slow to point out that we erect a building inside the scaffolding, not on the top of the scaffolding; and if we did erect a building on the top of our scaffolding, we could not take the scaffolding away without letting the building fall to the ground. Our own parable has been turned against us.

It will be better to avoid the metaphor, and to keep in mind the distinction just mentioned. The motives of credibility, satisfying his intellect, bring the inquirer up to the point of making the act of faith. That act recognises God's authority in the Church's teaching; and the absolute nature of his authority does make all the difference to the kind of certitude with which, thenceforward, he holds the truths of Catholic doctrine. But this is inherent in the act of faith, not in the chain of proof by which the Catholic claim is established. Having made the act of faith, he cannot produce more or better arguments to convince his neighbour than he could have produced before. Apologetically, then, revealed truths have no higher certitude than the arguments by which the fact of revelation is established. The revealed proposition that there are Three Persons in the Blessed Trinity is not, apologetically, more certain than the statement (established in the first instance by private judgment) that our Lord left the charisma of infallibility to his Church.

The Catholic claim does not profess to be based on a mathematical certainty. The proposition "Things which are equal to the same thing are equal to one another" is evident in the sense that the contrary proposition is unthinkable. The proposition "Jesus of Nazareth suffered under Pontius Pilate" is not evident in that sense; the contrary proposition, in this case, does not defy our thought. In historical statements (and every revealed religion must depend, in the last resort, upon an historical statement) the highest kind of certainty you can attain is that which excludes reasonable doubt. That is the kind of proof which Catholicism claims for those preliminary considerations which it calls "the motives of credibility." And consequently no point of Catholic doctrine can claim anything better than this historical kind of proof. The absolute certainty with which we believe the teaching of the Church comes to us from the supernatural grace of faith, which transforms our reasoned conviction into a higher quality-- the water, as at Cana, is turned into wine. But for apologetic purposes a reasoned conviction is all we can offer to our neighbours; and it is this reasoned conviction which the present thesis attempts to maintain.
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