For Van Til, knowledege of truth is correspondence with God's idea of something. This fact which God knows exists within a set of relations to other facts. It is therefore not clearly either a "correspondence" theory of truth, nor purely a "coherentist" theory of truth:
In a way it might be well for us to call our position the Coherence Theory of Truth because we claim to have true coherence. Whether we call our position a correspondence theory or whether we call it a coherence theory, we have in each case to distinguish it sharply from the theories that have historically gone by these names. Accordingly, the determining factor must be a consideration of that which is most fundamental in our theory of correspondence or of coherence. Now this depends upon the question whether we have God’s knowledge in mind first of all, or whether we begin with human knowledge. For God, coherence is the term that comes first. There was coherence in God’s plan before there was any space-time fact to which his knowledge might correspond, or which might correspond to his knowledge. On the other hand, when we think of human knowledge, correspondence is of primary importance. If there is to be true coherence in our knowledge there must be correspondence between our ideas of facts and God’s ideas of these facts. Or rather we should say that our ideas must correspond to God’s ideas. Now since we are dealing with opponents who speak of human knowledge almost exclusively, we can perhaps best bring out the distinctiveness of our position by calling it the Correspondence Theory of Truth. An additional reason for this choice is that at the present time the old correspondence theory has pretty well died down, leaving the coherence theory in control of the field. Hence we have the advantage of a different name from the current name, since we are interested in making it clear that we really have a different theory from the current theory(Van Til, "A Survey of Christian Epistemology").
So the Stanford Encyclopedia of Philosophy on the coherentist theory of truth:
A coherence theory of truth states that the truth of any (true) proposition consists in its coherence with some specified set of propositions. The coherence theory differs from its principal competitor, the correspondence theory of truth, in two essential respects. The competing theories give conflicting accounts of the relation that propositions bear to their truth conditions. (In this article, ‘proposition’ is not used in any technical sense. It simply refers to the bearers of truth values, whatever they may be.) According to one, the relation is coherence, according to the other, it is correspondence. The two theories also give conflicting accounts of truth conditions. According to the coherence theory, the truth conditions of propositions consist in other propositions. The correspondence theory, in contrast, states that the truth conditions of propositions are not (in general) propositions, but rather objective features of the world.(Young, 2013).
For Van Til, the "set" of propositions which makes any fact "true" is the sum total of its relations it bears to the rest of the world, and comprehensive knowledge of this fact (and thus of the relations it bears to all other facts) resides solely in God's mind. But does this mean that we must be omniscient in order to know anything? Obviously this is a conclusion Van Til wants to avoid. It is for this reason that he accepts 'degrees' of truth typically of idealist philosophers. Thus:
True human knowledge corresponds to the knowledge which God has of himself and his world. Suppose that I am a scientist investigating the life and ways of a cow. What is this cow? I say it is an animal. But that only pushes the question back. What is an animal? To answer that question I must know what life is. But again, to know what life is I must know how it is related to the inorganic world. And so I may and must continue till I reach the borders of the universe. And even when I have reached the borders of the universe, I do not yet know what the cow is. Complete knowledge of what a cow is call be had only by an absolute intelligence, i.e., by one who has, so to speak, the blueprint of the whole universe. But it does not follow from this that the knowledge of the cow that I have is not true as far as it goes. It is true if it corresponds to the knowledge that God has of the cow(Van Til, "A Survey of Christian Epistemology").
Because we lack the omniscience to know the relation of the cow to all other facts of the universe, we do not know completely what a cow is. Knowledge of truth is a question of degrees. Precision in language is thus a question of relative precision of qualitative degree, and knowledge of particular facts, a question of relative comprehensiveness in scope, rather than an issue of "either/or." This is in stark contrast to the epistemological views of Gordon Clark:
Also fixed in Scripture are the two other principle laws of logic: the law of identity (A is A), and the law of the excluded middle (A is either B or non-B). The former is taught in Exodus 3:14, in the name of God itself: “I AM WHO I AM.” And the latter is found, for example, in the words of Christ: “He who is not with me is against me” (Luke 11:23)(Crampton).
The law of excluded middle is of particular interest for us. For Clark, there are no degrees of knowledge of the truth of a particular fact. Of course, we do not know everything. But given a certain proposition, it is either true or false. If our belief about a proposition corresponds with its actual truth-value, then we "know" it. If not, then not. Knowledge of truth for Clark is an either/or scenario. Suppose I know that 1 + 1 = 2. It is a true proposition to which I assent. Therefore, I have knowledge of it. Do I have comprehensive knowledge of the relation that fact bears to all other facts? Of course not. I am not God. But I do have knowledge of that fact.
Gordon was absolutely insistent that we did know some of the same things that God knew. If not, he insisted, it would be impossible for us to know any truth at all! That 2 plus 2 equals 4 is true, he felt. Thus he insisted that in and of itself it is true as a statement without the necessity of examining another proposition. He carefully insisted upon a propositional concept of truth while Van Til insisted upon the fact that to have truth in one's mind that mind must be built upon other propositions. The truthfulness or falsity demanded that the individual proposition be held in the midst of certain other basic propositions that must be consciously present in that mind in order to correctly know truth. Now, of course, God knows every proposition in the context of all other propositions for Van Til, and, therefore, the limited human mind never knows it the way God does. Van Til had an expression..."true as far as it goes," meaning, of course, that for that mind which holds all propositions in a system, the more complete the system, the more full the truth. With growth in the knowledge of basic propositions, the further than mind had the truth. Van Til's concept is that for relative human beings, they can have all needful truth but never perceive it as God does with his infinite knowledge of everything that affects any proposition. He charged Clark, therefore, with denying the incomprehensibility of God and Clark charged him with agnosticism since he that that for him it was impossible to know anything as God did. Clark wanted an absolute even if it were only in the single proposition. (Gordon Clark: Personal Recollections, pgs. 103-104)
I think the key is "Van Til had an expression..."true as far as it goes," meaning, of course, that for that mind which holds all propositions in a system, the more complete the system, the more full the truth." It may indeed be that a proposition only exists within a system of other mutual reinforcing and mutually dependent propositions. Indeed, Clark accepted such a thing:
That relations are internal, and especially that the truth is the whole, are themes hard to deny. Yet their implications are devastating. So long as you or I do not know the relationships which constitute the meaning of cat or self, we do not know the object in question. If we say that we know some of the relationships – e.g., a cat is not-a-dog and admit that we do not know other relationships – e.g., a cat is not-an-(animal we have never heard of before) – it follows that we cannot know how this unknown relationship may alter our view of the relationship we now say we know. The alteration could be considerable. Therefore we cannot know even one relationship without knowing all. Obviously we do not know all. Therefore we know nothing.
This criticism is exceedingly disconcerting to an Hegelian, for its principle applies not merely to cats, dogs, and selves, but to the Absolute itself. The truth is the whole and the whole is the Absolute. But obviously we do not know the whole; we do not know the Absolute. In fact, not knowing the Absolute, we cannot know even that there is an Absolute. But how can Absolute Idealism be based on absolute ignorance? And ours is absolute ignorance, for we cannot know one thing without knowing all. (Christian Philosophy, pg. 153)
Undoubtedly I hold that truth is a consistent system of propositions. Most people would be willing to admit that two truths cannot be contradictories; and I would like to add that the complex of all truths cannot be a mere aggregate of unrelated assertions. Since God is rational, I do not see how any item of his knowledge can be unrelated to the rest. Weaver makes no comment on this fundamental characteristic of divine truth (Clark and His Critics, 2009, pg. 290)
Absolutism, and theism, too, hold that everything must be related to everything else in some way; there are no two things utterly independent, though in spite of Lotze, they may nonetheless be distinct. (Modern Philosophy, 2008, pg. 288)
One of the main points that the present volume wants to emphasize is the necessary logical connection of every proposition in an intellectual system with every other. (Historiography: Secular and Religious, 1971, pg. 179)
…this entire volume has been insisting that everything is connected with everything else. (Historiography: Secular and Religious, 1971, pg. 183)
William James, in his A Pluralistic Universe stressed the disconnectedness of things. Wholes are to be explained by parts and not parts by wholes, he said; one group of events, though interrelated among themselves, may be unrelated to another group; there is no dominating unity – however much may be reported as present at any effective center of consciousness, something else is self-governed, absent, and unreduced to unity. In one place James denied the need of answering a question that many others have thought as important as it is difficult: “Not why evil should exist at all, but how we can lessen the actual amount of it, is the sole question we need there to consider.” Of course, if a question is literally meaningless (such as, why is music oblong?) it is really not a question at all and does not need to be answered. But if a question is not senseless, by what right can a philosophy rule it out of court? Even if it were quite trivial, it should find its place and its answer in some minor subdivision of the truth. Then, too, one might ask how James discovered that some groups of events are unrelated to other groups? Or, more exactly, since he allowed “external” relations and denied only “internal” relations, one might ask how James could discover that something is absent from and unreduced to unity by every effective center of consciousness? In other words, did James have a valid argument for the conclusion that there is no Omniscient Mind whose thought is systematic truth? He may then be caught on the horns of the dilemma he tried to escape. Irrational chaos and Hegelian monism were equally repellent to him. He wanted to find a middle ground. But perhaps there is no escape from irrational chaos except, not exactly Hegelian monism, but a logical completeness of some sort. It would be surprising, would it not, if social stability could be based on incoherence, or even large-scale disconnectedness?
At any rate, the suspicion that the introductory questions are all related and that an answer to any one of them affects the answer to every other would accord with the theistic belief in divine omniscience. The discouragement, the reflection, the suspicion of the previous pages do not prove or demonstrate the existence of an omniscient God; but if there is such a God, we may infer that all problems and all solutions fit one another like pieces of a marvelous mosaic. The macrocosmic world with its microcosmic but thoughtful inhabitant will not be a fortuitous aggregation of unrelated elements. Instead of a series of disconnected propositions, truth will be a rational system, a logically-ordered series, somewhat like geometry with its theorems and axioms, its implications and presuppositions. Each part will derive its significance from the whole. Christianity therefore has, or, one may even say, Christianity is a comprehensive view of all things: It takes the world, both material and spiritual, to be an ordered system. Consequently, if Christianity is to be defended against the objections of other philosophies, the only adequate method will be comprehensive. While it is of great importance to defend particular points of special interest, these specific defenses will be insufficient. In addition to these details, there is also needed a picture of the whole into which they fit. This comprehensive apologia is seen all the more clearly to be necessary as the contrasting theories are more carefully considered. The naturalistic philosophy that engulfs the modern mind is not a repudiation of one or two items of the Christian faith leaving the remainder untouched; it is not a philosophy that is satisfied to deny miracles while approving or at least not disapproving of Christian moral standards; on the contrary, both Christianity and naturalism demand all or nothing: Compromise is impossible. At least this will be true if the answer of any one question is integral with the answers of every other. Each system proposes to interpret all the fact; each system subscribes to the principle that this is one world. A universe, even James’ pluralistic universe, cannot exist half-theistic and half-atheistic. Politics, science, and epistemology must all be one or the other.
The hypothesis of divine omniscience, the emphasis on the systematic unity of all truths, and the supposition that a particular truth derives its meaning or significance from the system as a whole does not imply that a man must know everything in order to know anything. It might at first seem to; and Plato, who faced the same difficulty, tried to provide for two kinds of knowing so that in one sense a man might know everything and in another sense not know and learn a particular truth. At the moment, let an illustration suffice. To appreciate an intricate and beautiful mosaic, we must see it as a whole; and the parts are properly explained only in terms of the whole; but it does not follow that a perception of the pieces and some fragmentary information is impossible without full appreciation. Or to pass from illustration to reality: A child in first grade learns that two plus two is four. This arithmetical proposition is true, and the greatest mathematician cannot disprove it. But the mathematician sees this truth in relation to a science of numbers he understands how this sum contributes to phases of mathematics that the child does not dream of and may never learn; he recognizes that the significance of the proposition depends on its place in the system. But the child in school knows that two and two are four, and this that that child knows is true. Omniscience, even higher mathematics, is not a prerequisite for first grade. (A Christian View of Men and Things, 2005, pgs. 22-24)
Is any proposition true in isolation? Would an atom by itself be the same regardless of how the rest of the world might change? There are plausible examples that it would not. Here is a rock that weighs six pounds. But if an astronaut carries it into space it weighs approximately zero. When he drops it on the Moon, it weighs one pound. The truth of these propositions depends of the relation of the rock to the other parts of the universe. No one is true in isolation. Obesity is cured by a trip to the Moon.
Another example is a piece of canvas painted half red and half green – or any other two colors. Through these two halves of the canvas paint a stroke of gray, a mixture of black and white; but it will not be gray on the canvas. The single stoke of paint will be one color on the top half and a different color on the bottom half. Since everything seen has a background, its color is a function of its background. It is false to say it remains what it is no matter how the rest of the universe changes.
One further example. If there were no sense of sight, there would be no sense of hearing. If there were nothing hard, there would be nothing soft. If there were no animals, there could be no plants. The reason is that each of these terms expresses a distinction from its opposites. Sight is a form of non-hearing. Were they the same, we might have the term sensation, but we would not have two terms of different meaning. The terms “plant” and “animal” would not apply to different objects, if there were no different objects. There might be “living beings,” but no plants and animals. Similarly, there would be no living beings, if there were no non-living beings. This should be sufficient to dispose of logical atomism. (Modern Philosophy, 2008, pg. 175)
Clark here is refuting the Hegelian doctrine of internal relations. According to this view, things are not merely internally related to one another, but rather, are so essentially bound up with one another that they cannot truly be understood at all isolated from their context. If this is the case, then obviously we cannot know anything unless we are God:
Reenactment of a thought is possible, nonetheless, because it can be separate from this immediacy without alteration. Not only so, it can be separated from other thoughts without alteration. Thus history becomes possible. This self-identity of the act of thought has been denied by two extreme views. The first view is that of idealism, the theory of internal relations, the notion that everything is what it is because of its context. This makes history impossible. To know any one thing it would be necessary to know its context; i.e. to know the whole universe. Knowledge would thus be restricted to the explicit consciousness of the omniscient Absolutes; and Collingwood, though he may be Beckett, does not claim to be the Absolute(Historiography: Secular and Religious on pgs. 225-226 (1971).
Note what Clark said before about the importance that we are able to have partial knowledge by abstracting a proposition from its context. Since we cannot know anything apart from its context, and since its entire context consists of the sum total of all facts to which it is related, it follows that either we cannot know anything, or we must possess knowledge in a manner qualitatively different from the way God knows it, because for all we know, if a proposition can only be fully understood in light of its full context, the relations which it bears to other propositions may cause the fact to be profoundly different than our knowledge of it. Since this is the case, when the doctrine of internal relations is taken to its logical conclusion, we cannot know anything at all. For Clark, it is true that all propositions only exist in relation to all other propositions, but we still must be able to fully affirm or deny a proposition by being able to abstract it from its context, even if we do not know the sum total of its relations to all other propositions.
But why did Van Til adopt such an apparently strange conclusion? I believe the answer lies in understanding the idealistic philosophy in which he was steeped throughout his life and intellectual career.
Cornelius Van Til completed his doctoral work at Princeton University in 1927 with a dissertation entitled "God and the Absolute," in which he argued that the God of Christian theism could not be identified with the Absolute of philosophical idealism. A couple of years later he had completed his Th.M. at Princeton Theology Seminary...The philosophy department at Princeton University at that time was under the direction of the British idealist Archibald Allen Bowman. Van Til's own interest in philosophy, and in particular idealism, had begun during his undergraduate days at Calvin College. There the philosophy department had consisted of only one instructor, W. Harry Jellema, who was himself only a couple of years older than Van Til...Jellema began teaching at Calvin in 1920, while working on his dissertation on Josiah Royce at the University of Michigan...One of the textbooks which he used for the undergraduate courses in philosophy at Calvin was F.H. Bradley's Appearance and Reality, to which Van Til would continue to refer in his later writings on idealist philosophy.
The influence of Bradley's idealistic philosophy upon Van Til seems to have been considerable, and is discussed in detail below. Indeed, Van Til himself acknowledged the formal similarity of his epistemological system with that of the idealists:
In opposition to the historical correspondence theory of truth there arose in the Kant-Hegel tradition the so-called Coherence Theory of Truth. The Idealists argued in the way that we have argued above about the cow. They said that true knowledge cannot be obtained by a mere corresopndence of an idea of the mind to all object existing apart from the mind. The mind and the object of which it seeks knowledge are parts of one great system of reality and one must have knowledge of the whole of this reality before one has knowledge of any of its parts. Accordingly, the Idealists said that the thing that really counted in knowledge was the coherence of any fact with all other facts. To know the place of a fact in the universe as a whole is to have true knowledge. This position, as we shall see more fully later, approaches, in form, what we are after in our position. Yet it is only in form that it approaches our position. That this istrue can be seewn from the determining fact that the Absolute to which the Idealist seeks to relate all knowledge is not the completely self-conscious God of Christianity. We cannot prove this point here. W only state it as our conviction here in order to clear the ground. The Absolute oef Idealism, we believe, is not an absolute because he exists as merely correlative to the space-time world. Accordingly there are new facts arising for hima s well as for us. God becomes a primus inter pares, a One among others. He can no longer be the standard of human knowledge(Van Til, "A Survey of Christian Epistemology").
Of particular importance for Van Til was the previously mentioned idealist philosopher, F.H. Bradley, and his concept of relative truth. The historical context in which Bradley developed his epistemological views involved what he saw as a false dichotomy between the certain knowledge to which traditional epistemologists aspired, and the radical skepticism of those who rejected such (supposed) pretensions to knowledge: "According to the absolute view [of truth], as we have seen, truth and falsity are exclusive alternatives. Propositions or theories must be regarded as either absolutely true or absolutely false. Neither alternative is satisfactory"(Sayers). But why did Bradley take such a view? An analogy of scientific justification will help us understand why:
Let us consider thte status of current scientific beliefs and theories...Can these theories be regarded as embodying absolute truth? Certainly not. That would be to suggest that the areas of knowledge concerned are complete and perfect, and that no further investigation could ever lead us to change our views of them. There is no valid basis for this sort of claim in chemistry, physics, or, kindeed, in any other area of scientific knowledge. Quite the contrary. If we look back over, say, the past 200 years, it is evident that scientific understanding has been advancing at a rapid and ever accelerating pace. Phlogiston theory has been replaced by modern chemistry; and Newtonian mechanics and physics have been superseded by the theory of relativity and quantum theory. Similar strides have been made in other areas. Whole new fields of scientific knowledge have been discovered and opened up.
Moreover, there seems every reason to believe that such developments will continue, with at least an equal rapidity in the next 200 years. In 200 years time it seems likely that scientists will look back on our views as we now look back on the scientific ideas of the eighteenth century. In other words, current scientific theories are almost certain to be superseded and discarded. They cannot, therefore, be regarded as absolute truths.
Indeed, in time they are almost certain to be regarded as false. According to the traditional approach, it would seem that we should therefore now regard them as absolutely false. But that is, if anything, an uneven more unsatisfactory view. Although, no doubt, our current understanding is partial, limited and destined in time to be superseded, we have some grasp of the truth, some understanding of the natural world, to which no jutice is done by the assertion that current theories are merely false. One current understanding embodies considerable knowledge of the natural world. It is the result of a long process of previous scientific development, and in its turn it provides the essential basis upon which better theories, still to come, will build and develop. Likewise, previous and now superseded views - like phlogiston chemistry or Newtonian mechanics - should not be regarded as mere errors and illusions. These theories have played an essential role in the development of knowledge. They constitute the basis upon which our present views were built. They contained some measure of understanding of the world, some (albeit partial) validity and truth.
In short, neither current beliefs nor previous ones are either absolutely true or absolutely false. These abstract - absolute and metaphysical - categories are a hinderance to understanding and should be discarded in the theory of knowledge. However, this is not to say that we must embrace a sceptical or relativist position and reject the ideas of turth and error altogether. For we can and must maintain, of some mof our beliefs at any rate, that they are true relatively. For this stage of our development, current chemistry and physics are necessary and jutified sets of beliefs. Such theories are not merely possible 'ways of seeing things', as relativism suggests. Rather, they represent the best accounts of these areas presently available. There are no other equally valid, or equally possible, alternative theories in these areas.
Relative to previous theories and other presently available alternatives, modern chemistry and physics are the most satisfactory accounts of their objects so far developed. It is such an essentially relative judgement that we make when we say that our current beliefs are 'true', 'objective', 'rational', or 'scientifically jutified'. Thus our beliefs are justified relatively, not absolutely. But relatively, they are justified. This justification, though relative is, as Bradley says, real(Sayers).
The problem with what Sayers says here is that he does not adequately distinguish between knowledge and truth, at times conflating them. It is certainly entirely possible that some of our scientific beliefs are "true." However, our belief in their truth can never be ultimately justified precisely because of the defeasibility of these beliefs. Scientific fallibilism precludes scientific knowledge. Our beliefs may be true beliefs. But because they cannot be justified, they cannot count as knowledge. It is of course true that because of a certain pragmatic necessity, we are required to act as though our beliefs are indubitable, and therefore justified, and therefore knowledge (keeping in mind that from the Clarkian perspective, indubitability is an essential component of epistemic justification, and therefore, of knowledge):
Although not usually recognized as such, a certain claim to infallibility meets us in our everyday affairs. When an accountant balances his books, does he not assume that his figures are correct? When a college professor hurries to class for fear that his students will disappear if he is late, does he not make judgments as to the time of day and the proclivities of students? When a chess club challenges another to a match, does any suspicion of fallibility impede its action? Cannot this club distinguish the dogma ecclesiastica that there actually is another club from the dogma haeretica that no other club exists? Must not all people act on the assumption that their beliefs are true? (Clark, Karl Barth’s Theological Method, 1997 pg. 146)
But these apparently reliable opinions can never constitute knowledge. For Clark, there is no such thing as relative truth. Truth is simply truth. It is either truth or it is falsity, without degrees of truth or falsity. Hence the importance of the law of excluded middle. We may speak of relative knowledge, but it is "relative" to God's absolute knowledge. Our own knowledge is relatively partial because we only know facts isolated from their total context; that is, we only know facts isolated from their relation to all other facts. But the proposition which constitutes partial knowledge relative to its relation to all other facts is itself either straightforwardly true or false.
As Van Til points out, an essential conflict arises between Christianity and Absolute Idealism insofar as the progress of Absolute Mind takes place within history itself, rather than utterly transcending it, as in the case of the Triune God. Indeed, it is in Bradley's view of the progress of influence, and of the resolution of contradictories by each successive phase, that the Hegelian influence upon his thought is perhaps most clear.
Bradley...sees the development of knowledge as a process in which each stage is necessary and justified - and hence true - for its time; but in which each stage ultimately gives way to a new and higher stage which emerges from it, and on its basis. In that sense, the development is a progressive one(Sayers, p. 12).
More explicitly teleological than Bradley in his writing is the master Hegel himself, as Sayers notes:
Thus the history of thought, as Hegel says, 'in its results resembles not a museum of the aberrations of the human intellect, but a Pantheon of Godlike figures.' Moreover, according to this view, truth is actually realized at every stage of the development, as well as continually in the process of being realized in new and higher forms. Hegel makes this point, in a different t hough related context, when he writes that 'the final purpose of the world is accomplished no less than ever accomplishing itself'(Sayers, pp. 12-13)
Young, James O., "The Coherence Theory of Truth", The Stanford Encyclopedia of Philosophy (Summer 2013 Edition), Edward N. Zalta (ed.), URL = <plato.stanford.edu/archives/sum2013/entries/truth-coherence/>.
Sayers, Sean. F.H. Bradley and the Concept of Relative Truth. Retrieved from: http://www.kent.ac.uk/secl/philosophy/articles/sayers/bradley.pdf
Mcconnel, Timothy. The Influence of Idealism on the Apologetics of Cornelius Van Til. JETS 48/3 (September 2005) 557-88. Retrieved from: http://www.etsjets.org/files/JETS-PDFs/48/48-3/JETS_48-3_557-588.pdf