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Logic and the Foundations of Protestant Faith

Brian W. Harrison
May 16, 2011 4 Comments

As an active Protestant in my mid-twenties I began to feel that I might have a vocation to become a minister. The trouble was that while I had quite definite convictions about the things that most Christians have traditionally held in common — the sort of thing C.S. Lewis termed “mere Christianity” — I had had some firsthand experience with several denominations (Presbyterian, Anglican, Lutheran, Methodist) and was far from certain as to which of them (if any) had an overall advantage over the others. So I began to think, study, search, and pray. Was there a true Church? If so, how was one to decide which?

The more I studied, the more perplexed I became. At one point my elder sister, a very committed evangelical with somewhat flexible denominational affiliations, chided me with becoming “obsessed” with trying to find a “true Church.” “Does it really matter?” she would ask. Well, yes it did. It was all very well for a lay Protestant to relegate the denominational issue to a fairly low priority amongst religious questions: lay people can go to one Protestant church one week and another the next week and nobody really worries too much. But an ordained minister obviously cannot do that. He must make a serious commitment to a definite church community, and under normal circumstances that commitment will be expected to last a lifetime. So clearly that choice had to be made with a deep sense of responsibility; and the time to make it was before, not after, ordination.

As matters turned out, my search lasted several years, and eventually led me to where I never suspected it would at first. I shall not attempt to relate the full story, but will focus on just one aspect of the question as it developed for me — an aspect which seems quite fundamental.

As I groped and prayed my way towards a decision contemplating the mountains of erudition, the vast labyrinth of conflicting interpretations of Christianity (not to mention other faiths) which lined the shelves of religious bookshops and libraries I at times came close to despair and agnosticism. If all the “experts” on truth — the great theologians, historians, philosophers — disagreed interminably with each other, then how did God, if He was really there, expect me, an ordinary “Joe Blow,” to work out what was true?

The more I became enmeshed in specific questions of biblical interpretation — of who had the right understanding of justification, of the Eucharist, Baptism, grace, Christology, Church government and discipline, and so on — the more I came to feel that this whole line of approach was a hopeless quest, a blind alley. These were all questions that required a great deal of erudition, learning, competence in biblical exegesis, patristics, history, metaphysics, ancient languages — in short, scholarly research. But was it really credible (I began to ask myself) that God, if He were to reveal the truth about these disputed questions at all, would make this truth so inaccessible that only a small scholarly elite had even the faintest chance of reaching it? Wasn’t that a kind of gnosticism? Where did it leave the nonscholarly bulk of the human race? It didn’t seem to make sense. If, as they say, war is too important to be left to the generals, then revealed truth seemed too important to be left to the biblical scholars. It was no use saying that perhaps God simply expected the non-scholars to trust the scholars. How were they to know which scholars to trust, given that the scholars all contradicted each other?

Therefore, in my efforts to break out of the dense exegetical undergrowth where I could not see the trees for the wood, I shifted towards a new emphasis in my truth-seeking criteria: I tried to get beyond the bewildering mass of contingent historical and linguistic data upon which the rival exegetes and theologians constructed their doctrinal castles, in order to concentrate on those elemental, necessary principles of human thought which are accessible to all of us, learned and unlearned alike. In a word, I began to suspect that an emphasis on logic, rather than on research, might expedite an answer to my prayers for guidance.

The advantage was that you don’t need to be learned to be logical. You need not have spent years amassing mountains of information in libraries in order to apply the first principles of reason. You can apply them from the comfort of your armchair, so to speak, in order to test the claims of any body of doctrine, on any subject whatsoever, that comes claiming your acceptance. Moreover logic, like mathematics, yields firm certitude, not mere changeable opinions and provisional hypotheses. Logic is the first natural “beacon of light” with which God has provided us as intelligent beings living in a world darkened by the confusion of countless conflicting attitudes, doctrines and world-views, all telling us how to live our lives during this brief time that is given to us here on earth.

Logic of course has its limits. Pure “armchair” reasoning alone will never be able to tell you the meaning of your life and how you should live it. But as far as it goes, logic is an indispensable tool, and I even suspect that you sin against God, the first truth, if you knowingly flout or ignore it in your thinking. “Thou shalt not contradict thyself” seems to me an important precept of the natural moral law.

Be that as it may, I found that the main use of logic, in my quest for religious truth, turned out to be in deciding not what was true, but what was false. If someone presents you with a system of ideas or doctrines which logical analysis reveals to be coherent — that is, free from internal contradictions and meaningless absurdities — then you can conclude, “This set of ideas may be true. It has at least passed the first test of truth — the coherence test.” To find out if it actually is true you will then have to leave your logician’s armchair and seek further information. But if it fails this most elementary test of truth, it can safely be eliminated without further ado from the ideological competition, no matter how many impressive-looking volumes of erudition may have been written in support of it, and no matter how attractive and appealing many of its features (or many of its proponents) may appear.

Some readers may wonder why I am laboring the point about logic. Isn’t all this perfectly obvious? Well, it ought to be obvious to everyone, and is indeed obvious to many, including those who have had the good fortune of receiving a classical Catholic education. Catholicism, as I came to discover, has a quite positive approach to our natural reasoning powers, and traditionally has its future priests study philosophy for years before they even begin theology. But I came from a religious milieu where this outlook was not encouraged, and was often even discouraged. The Protestant Reformers taught that original sin has so weakened the human intellect that we must be extremely cautious about the claims of “proud reason.” Luther called reason the “devil’s whore” — a siren which seduced men into grievous error. “Don’t trust your reason, just bow humbly before God’s truth revealed to you in His holy Word, the Bible!” — this was pretty much the message that came through to me from the Calvinist and Lutheran circles that influenced me most in the first few years after I made my “decision for Christ” at the age of 18. The Reformers themselves were forced to employ reason even while denouncing it, in their efforts to rebut the biblical arguments of their “Papist” foes. And that, it seemed to me, was rather illogical on their part.

Logic And The Sola Scriptura Principle

Thus, with my awakening interest in logical analysis as a test of religious truth, I was naturally led to ask whether this illogicality in the practice of the Reformers was, perhaps, accompanied by illogicality at the more fundamental level of their theory. As a good Protestant I had been brought up to hold as sacred the basic methodological principle of the Reformation: that the Bible alone contains all the truth that God has revealed for our salvation. Churches that held to that principle were at least “respectable,” one was given to understand, even though they might differ considerably from each other in regard to the interpretation of Scripture. But as for Roman Catholicism and other churches which unashamedly added their own traditions to the Word of God — were they not self-evidently outside the pale? Were they not condemned out of their own mouths?

But when I got down to making a serious attempt to explore the implications of this rock-bottom dogma of the Reformers, I could not avoid the conclusion that it was rationally indefensible. This is demonstrated in the following eight steps, which embody nothing more than simple, common sense logic, and a couple of indisputable, empirically observable facts about the Bible:

1. The Reformers asserted Proposition A: “All revealed truth is to be found in the inspired Scriptures.” However, this is quite useless unless we know which books are meant by the “inspired Scriptures.” After all, many different sects and religions have many different books, which they call “inspired Scriptures.”

2. The theory we are considering, when it talks of “inspired Scriptures,” means in fact those 66 books, which are bound and published in Protestant Bibles. For convenience we shall refer to them from now on simply as “the 66 books.”

3. The precise statement of the theory we are examining thus becomes Proposition B: “All revealed truth is to be found in the 66 books.”

4. It is a fact that nowhere in the 66 books themselves can we find any statements telling us which books make up the entire corpus of inspired Scripture. There is no complete list of inspired books anywhere within their own pages, nor can such a list be compiled by putting isolated verses together. (This would be the case: (a) if you could find verses like “Esther is the Word of God,” “This Gospel is inspired by God,” “The Second Letter of Peter is inspired Scripture,” etc., for all of the 66 books; and (b) if you could also find a biblical passage stating that no books other than these 66 were to be held as inspired. Obviously, nobody could even pretend to find all this information about the canon of Scripture in the Bible itself.)

5. It follows that Proposition B — the very foundation of all Protestant Christianity — is neither found in Scripture nor can be deduced from Scripture in any way. Since the 66 books are not even identified in Scripture, much less can any further information about them (e.g., that all revealed truth is contained in them) be found there. In short, we must affirm Proposition C: “Proposition B is an addition to the 66 books.”

6. It follows immediately from the truth of Proposition C that Proposition B cannot itself be revealed truth. To assert that it is would involve a self-contradictory statement: “All revealed truth is to be found in the 66 books, but this revealed truth itself is not found there.”

7. Could it be the case that Proposition B is true, but is not revealed truth? If that is the case, then it must be either something which can be deduced from revealed truth or something which natural human reason alone can discover, without any help from revelation. The first possibility is ruled out because, as we saw in steps 4 and 5, B cannot be deduced from Scripture, and to postulate some other revealed extra-Scriptural premise from which B might be deduced would contradict B itself. The second possibility involves no self-contradiction, but it is factually preposterous, and I doubt whether any Protestant has seriously tried to defend it — least of all those traditional Protestants who strongly emphasize the corruption of man’s natural intellectual powers as a result of the Fall.

Human reason might well be able to conclude prudently and responsibly that an authority which itself claimed to possess the totality of revealed truth was in fact justified in making that claim, provided that this authority backed up the claim by some very striking evidence. (Catholics, in fact, believe that their Church is precisely such an authority.) But how could reason alone reach that same well-founded certitude about a collection of 66 books which do not even lay claim to what is attributed to them? (The point is reinforced when we remember that those who attribute the totality of revealed truth to the 66 books, namely Protestant church members, are very ready to acknowledge their own fallibility — whether individually or collectively — in matters of religious doctrine. All Protestant churches deny their own infallibility as much as they deny the Pope’s.)

8. Since Proposition B is not revealed truth, nor a truth which can be deduced from revelation, nor a naturally-knowable truth, it is not true at all. Therefore, the basic doctrine for which the Reformers fought is simply false.

Calvin’s Attempted Solution

How did the Reformers try to cope with this fundamental weakness in the logical structure of their own first principles? John Calvin, usually credited with being the most systematic and coherent thinker of the Reformation, tried to justify belief in the divine authorship of the 66 books by dogmatically postulating a direct communication of this knowledge from God to the individual believer. Calvin makes it clear that in saying Scripture is “self-authenticated,” he does not mean to be taken literally and absolutely. He does not mean that some Bible text or other affirms that the 66 books, and they alone, are divinely inspired. As we observed in step 4 above, nobody ever could claim anything so patently false. Calvin simply means that no extra-biblical human testimony, such as that of Church tradition, is needed in order for individuals to know that these books are inspired. We can summarize his view as Proposition D: “The Holy Spirit teaches Christians individually, by a direct inward testimony, that the 66 books are inspired by God.”

The trouble is that the Holy Spirit Himself is an extra-biblical authority as much as a Pope or Council. The third Person of the Trinity is clearly not identical with the truths He has expressed, through human authors, in the Bible. It follows that even if Calvin’s Proposition D is true, it contradicts Proposition B, for “if all revealed truth is to be found in the 66 books,” then that leaves no room for the Holy Spirit to reveal directly and non-verbally one truth which cannot be found in any passage of those books, namely, the fact that each one of them is inspired.

In any case, even if Calvin could somehow show that D did not itself contradict B, he would still not have succeeded in showing that B is true. Even if we were to accept the extremely implausible view represented by Proposition D, that would not prove that        

no other writings are inspired, and much less would it prove that there are no revealed truths that come to us through tradition rather than through inspired writings. In short, Calvin’s defense of biblical inspiration in no way overthrows our eight-step disproof of the sola Scriptura principle. Indeed, it does not even attempt to establish that principle as a whole, but only one aspect of it — that is, which books are to be understood by the term “Scriptura.”

The schizoid history of Protestantism itself bears witness to the original inner contradiction which marked its conception and birth. Conservative Protestants have maintained the original insistence on the Bible as the unique infallible source of revealed truth, at the price of logical incoherence. Liberals on the other hand have escaped the incoherence while maintaining the claim to “private interpretation” over against that of popes and Councils, but at the price of abandoning the Reformers’ insistence on an infallible Bible. They thereby effectively replace revealed truth by human opinion, and faith by an autonomous reason. Thus, in the liberal/evangelical split within Protestantism since the 18th century, we see both sides teaching radically opposed doctrines, even while each claims to be the authentic heir of the Reformation. The irony is that both sides are right: their conflicting beliefs are simply the two horns of a dilemma, which has been tearing at the inner fabric of Protestantism ever since its turbulent beginnings.

Reflections such as these from a Catholic onlooker may seem a little hard or unyielding to some — ill-suited, perhaps, to a climate of ecumenical dialogue in which gentle suggestion, rather than blunt affirmation, is the preferred mode of discourse. But logic is of its very nature hard and unyielding; and insofar as truth and honesty are to be the hallmarks of true ecumenism, the claims of logic will have to be squarely faced, not politely avoided.


Brian W. Harrison

The Rev. Brian W. Harrison, O.S., M.A., S.T.D., a priest of the Society of the Oblates of Wisdom, is an emeritus professor of theology of the Pontifical Catholic University of Puerto Rico in Ponce.


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