Made for Truth: Bl. John Henry Newman and the Question of Certainty


To live today as a follower of Christ is to be exposed to the question of certainty. Can we really be certain that the Faith comes from God? Can we come to accept, without qualification, doubt, or intellectual distance, that Jesus’ teaching was an authentic revelation? The apparent secularization of the West, the feeling that all beliefs are contestable, and an ambient modesty about the human intellect’s ability to know truth all combine to challenge certainty on such matters for those living in the West in the 21st century.

Bl. John Henry Cardinal Newman’s work An Essay in Aid of a Grammar of Assent sheds light on how we might approach aspects of this issue. Bl. Newman wrote the Grammar later in life, and it examined a topic he had long wanted to treat: certainty in religious belief. According to Fr. Philip Flanagan,1 the Grammar of Assent ought to be read in light of a correspondence Newman carried on with William Froude, a scientist and a friend of Newman’s. The two corresponded about the question of unqualified belief. Froude’s wife and four of their children became Catholics, but Froude himself never did, and a sticking point for him was what he perceived to be the gap between the absolute acceptance of Catholicism that Catholics held and the evidence adducible for Catholicism, which could never be such as to remove all admixture of doubt. Perhaps Catholicism was probable, even highly probable—but how could one ever be so certain of it as to believe without qualification that it is true?

In Flannigan’s telling, Froude held that one could only be certain of something that was either self-evident, or provable by “mathematical demonstration.” Thus he believed that absolute certainty was not possible in ordinary life, politics, history, and theology—and yet Catholics are expected to be certain in their adherence to the Catholic faith.

Locke and Newman

In the Grammar of Assent, Newman offers a critique of this theory by Froude, and he does so, as Fr. Flannnigan notes, by his discussion of John Locke;  Locke serves as a proxy for Froude’s epistemology in the Grammar.

Newman’s critique of Locke involves what Newman calls assent. For Newman, “assent” means a mental act that is “in itself the absolute acceptance of a proposition without any condition.” The path to such unconditional adherence, for Newman, passes through inference; Newman calls the act whereby we argue or supply evidence for a proposition “inference” and inference is always strictly “dependent” on the premises from which it proceeds. Assent follows inference, but transcends it, as it is a mental adherence that is unconditional. Assent is not a different way of referring to the same mental act of inference, but a different mental act, one that is not strictly tied to the reasoning involved in inference and simply holds that a given proposition is true. It does not allow for degrees; though an assent may be more or less “vivid,” strictly speaking we don’t give more or less assent to something. Either we assent (which is an absolute act) or we do not assent.2

According to Newman, Locke, however, holds a general theory in which assent does admit of degrees—that is, we give a stronger or weaker assent to propositions based on the evidence for them. For Locke, we should “not [entertain] any proposition with greater assurance than the proofs it is built on will warrant.”3 In critiquing this view, Newman notes that not even Locke consistently holds to it, for he allows for exceptions to his own rule:

Most of the propositions we think, reason, discourse, nay, act upon, are such as we cannot have undoubted knowledge of their truth; yet some of them border so near upon certainty, that we make no doubt at all about them, but assent to them as firmly, and act according to that assent as resolutely, as if they were infallibly demonstrated, and that our knowledge of them was perfect and certain.

So says Locke. Newman comments on this passage, stating that Locke here admits that there are cases in which inferences do not arrive at a certain conclusion, and yet we treat them as if they had.

“That is,” writes Newman, “he affirms and sanctions the very paradox to which I am committed myself.” Newman’s other quarrel with Locke is, then, over the scope of cases in which that kind of mental process is legitimate. According to Newman, Locke only allows for assent in certain circumscribed cases, in what Newman sees as an arbitrary limitation:

Instead of going by the testimony of psychological facts, and thereby determining our constitutive faculties and our proper condition, and being content with the mind as God has made it, he [Locke] would form men as he thinks they ought to be formed, into something better and higher, and calls them irrational and indefensible, if (so to speak) they take to the water, instead of remaining under the narrow wings of his own arbitrary theory.

That is, Newman thinks we must break from Locke in allowing much greater scope for the lawfulness of assent in many cases where some proposition has not been “infallibly demonstrated.” As Newman sees it, human beings do, as a matter of fact, arrive at such assent in many matters in which proof does not rise to the level of demonstration (either because demonstration, although possible, simply has not been done in a certain case, or because demonstration is not possible). We believe with certainty in historical matters, for example.

For Newman, then, assent is a fact of our existence and natural to us. “We do but fulfill our nature in doubting, inferring, and assenting; and our duty is, not to abstain from the exercise of any function of our nature, but to do what is in itself right rightly,” Newman writes early in the Grammar. And, while addressing Locke’s theory, he puts it thusly: “…[H]e [Locke] consults his own ideal of how the mind ought to act, instead of interrogating human nature, as an existing thing, as it is found in the world.” Consequently, for Newman, we should look to the nature of our minds and, allowing our minds to work according to it, welcome assent, as much as (for example) inference, as part of how we engage intellectually with the world.

Religion, Natural and Revealed

A skeptic of a certain stripe might argue that even if Newman’s epistemology works for ordinary matters, it’s out of court simply to transfer that theory over to the religious domain, since “extraordinary claims demand extraordinary evidence.” But if the human mind works by passing through inference to assent as a general matter, this is also, for Newman, how it works when it comes to religious questions like whether Christianity comes from God.

In the second part of the Grammar, Newman gives account of some of the personal reasons that lead him to belief in the divine origin of Christianity, providing a sort of example of his own thinking in action when applied to the question of the credibility of the claim that Christianity relays an authentic divine revelation. The arguments, which need not be gone into here, range from the fate of Judaism after the rejection of Christ by Israel to the conversion of the ancient pagan world to Christianity. But Newman prefaces these arguments with a helpful methodological note: Arguments for Christianity will not appear convincing to those who are not adherents of what Newman calls “natural religion,” which is the proper religious sense of mankind apart from the specific divine revelation imparted with Christianity:

I have no scruple in beginning the review I shall take of Christianity by professing to consult for those only whose minds are properly prepared for it; and by being prepared, I mean to denote those who are imbued with the religious opinions and sentiments which I have identified with Natural Religion…. It is plainly absurd to attempt to prove a second proposition to those who do not admit the first.

Newman lists several “opinions” which those who deny natural religion might hold. These include “that the Creator does not punish except in the sense of correcting,” “that miracles are impossible,” and “that prayer to Him is a superstition.” Those who hold these and other opinions are not properly prepared, according to Newman, to hear the case for Christianity. When, therefore, someone wishes to hold arguments for the divine origin of Christianity to a higher bar, it’s worth asking what presuppositions lay behind the bar she establishes. Is this person a theist? Does she have any prior religious sense? Does she admit the possibility, for example, that the God who exists can work miracles? If the answer to these question is in the negative, then she will not necessarily be disposed to see the cogency of the arguments for Christianity.

If extraordinary claims demand extraordinary evidence, in other words, what makes a claim seem extraordinary? For those who deny certain truths of natural religion, the claims of Christianity will seem more extraordinary than they do to those who accept natural religion—and who yearn for the fulfillment of mankind’s natural religious needs that is found in the life of grace in the Faith (such “preparation” is a theme for Newman, and is discussed by Fr. Flannigan).

Fallibility and Certitude

However, a general objection could be lodged against Newman’s theory, one which Newman explicitly entertains. Should we not recognize that humans are fallible, and thus that humans generally, and we specifically, are liable to be wrong about many kinds of matters? And if that is so, how can we really assent to something without any “alloy of doubt”? In our culture, there is an ambient sense that certainty about truth is a kind of arrogance, a mental vice by which people pretend to a greater knowledge of reality than they do or can have. This sense is more deeply felt in the realms of morality and religion: Fallible human beings cannot really know the Truth about such matters.

This was apparently true in Newman’s time as well, for here is how he phrases this objection:

And, as to the feeling of finality and security, ought it ever to be indulged? Is it not a mere weakness or extravagance, a deceit, to be eschewed by every clear and prudent mind? With the countless instances, on all sides of us, of human fallibility, with the constant exhibitions of antagonist certitudes, who can so sin against modesty and sobriety of mind, as not to be content with probability as the true guide of life, renouncing ambitious thoughts, which are sure either to delude him, or to disappoint?

Newman responds to this objection first by distinguishing between certitude and infallibility.4 “A certitude,” writes Newman, “is directed to this or that particular proposition; it is not a faculty or gift, but a disposition of mind relatively to a definite case which is before me. Infallibility, on the contrary, is just that which certitude is not; it is a faculty or gift, and relates, not to some one truth in particular, but to all possible propositions in a given subject-matter.” The Pope has infallibility in a restricted domain and under certain conditions, while human beings ordinarily do not—but this should not leave us to lay aside all certitudes in the name of human fallibility. For, as Newman sees it, fallibility and certainty are not mutually exclusive:

Certainly, the experience of mistakes in the assents which we have made are to the prejudice of subsequent ones. There is an antecedent difficulty in our allowing ourselves to be certain of something today, if yesterday we had to give up our belief of something else, of which we had up to that time professed ourselves to be certain. This is true; but antecedent objections to an act are not sufficient of themselves to prohibit its exercise; they may demand of us an increased circumspection before committing ourselves to it, but may be met with reasons more than sufficient to overcome them.

In teasing this out, Newman once again rests his account on human nature. Certitude, which he here defines as “a deliberate assent given expressly after reasoning,” is natural to humans; it belongs to our mental makeup to attain or extend certitude to those propositions at which our reasoning has clearly arrived. When a person’s reasoning had so arrived (as Newman puts it in the first person), “I could indeed have withheld my assent, but I should have acted against my nature, had I done so when there was what I considered a proof.”

That is, for Newman it is “fitting” that we extend certitude5 when we are faced with “what [we consider] a proof,” and it would be unfitting—against our nature—to do otherwise. For Newman, when we extend certitude wrongly based on what we take to be a proof, the error was with our reasoning, not with the certitude, which was correctly given. In that case, what we ought to do in the future is not withhold certitude but improve our reasoning, which precedes the act of certitude. And while, in improving our reasoning, we may become more cautious in the future, that caution is not, or should not be, indefeasible; reasoning can still go on and can still become clear or compelling enough to invite the act of certitude, which we ought then to extend.

One cannot offer an “antecedent objection” sufficient to overturn reasoning as such, and when our reasoning comes to a strong enough conclusion we would be acting against our nature if we withheld certitude. “Errors in reasoning are lessons and warnings,” writes Newman, “not to give up reasoning, but to reason with greater caution. It is absurd to break up the whole structure of our knowledge, which is the glory of the human intellect, because the intellect is not infallible in its conclusions.”

Certain Knowledge, Uncertain Feelings

For Newman, “the human mind is made for truth, and so rests in truth.” His account of how we do arrive at the unconditional state of adherence to some proposition—that is, how we assent—and how we can arrive at the further or higher state of certitude is both descriptive and prescriptive. He believes both that his account just is how our minds naturally work and that it is fitting that we follow our nature in accepting it as we have received it. To give up on unconditional adherence because of modesty, despair, or a desire to form the human person into “something better and higher” is to lose the “structure of our knowledge” that is “the glory of the human intellect.” Humans are fallible, and the structure of reality is such that we cannot scientifically demonstrate all truths. But these truths, for Newman, are not reasons to renounce certainty. Rather we should take them as spurs to “do what is right rightly”; to reason more carefully, not to renounce assent and certitude.

Certainty, however, is not just an intellectual question; when it comes to the Faith, it can be felt as an emotional and spiritual one, when we are vexed and anxious over truths we took ourselves to believe. In such circumstances, it may be helpful to note that certainty may be felt, but it is not reducible to any subjective reality. To lack the feeling of certainty is not to lack certainty, and to feel ill at ease about some belief is not to lose one’s assent to it. Assent can be extended in good times and in bad, in serenity and in intellectual or existential torment.

In such circumstances, we can take a page from St. Thérèse of Lisieux, another 19th-century figure, and offer this torment up as a sacrifice on behalf of those who do not believe, to give to God the sufferings that come from uncertain feelings for the sake of those who really lack belief. But that would be a topic for another occasion.


1 In his book Newman, Faith and the Believer. I’m grateful to Prof. Reinhard Huetter for recommending this book to me, and for clearing up one question raised for me by reading it.

2 Assent is not the same, for Newman, as certitude, for the latter is a self-consciousness or “reflex” act, “as expressed in the phrase, ‘I know that I know…’” But Newman allows that, in some cases, even simple assents that are not reflex can be classed as “material certitude; or, to use a still more apposite term for it, interpretative certitude.” In any case, establishing the legitimacy of unconditional and absolute assent would do the job I am after in this essay, even if it is not strictly speaking what Newman means by certitude.

3 These are Locke’s own words as quoted by Newman.

4 Again, for Newman, certitude and assent are not strictly the same thing; certitude is a kind of meta-assent. Newman holds that certitude, unlike assent, is as a general matter indefectible; once it is reached, it does not fail.

5 He uses both the word “assent” and the word “certitude” in this passage, but I’ve just gone with certitude here because of the context.

[This article appears in Fare Forward Issue 8 (Dec. 2017), order here.]

Peter Blair

Peter Blair lives in Washington, DC. A 2012 graduate of Dartmouth College, he works as Campus Program Coordinator for the Thomistic Institute. Peter is editor-in-chief of Fare Forward. He is on Twitter: @PeterAWBlair.