05 / 06

Perils of the Open Road

William Lane Craig

Used by permission of Faith and Philosophy 30 (2013):  49-71.


When the course of events can go in more than one direction, given present conditions, does God know which way it will go? Open theists deny that God has knowledge of such “future contingents.” They are prompted in large part by an estimable concern to safeguard human and divine freedom. This is a concern that we share. What we do not share with open theists is their conviction that divine foreknowledge must be restricted in order to make the world safe for genuine free agency. God’s foreknowledge, we believe, does not annul what would otherwise have been a free action, and denying foreknowledge does not secure for foreknown actions a freedom that was not otherwise in jeopardy.

A growing number of philosophers appear to think differently. Two recent defenses of open theism in this journal—one by Dale Tuggy and the other co-authored by Alan Rhoda, Gregory Boyd, and Tom Belt—provide evidence of the increasing attention and support that open theism is attracting in the philosophical literature. [1] Despite the diversity of our own viewpoints on a number of issues related to divine omniscience, [2]we are united in regarding the trend toward open theism as lamentable, and indeed, a bit baffling. In the following pages we explain why we believe that the arguments offered by Tuggy and Rhoda et al. should not persuade anyone to venture down the road to open theism.

Three Roads to Open Theism

We begin with Dale Tuggy’s article, since he provides a useful map of the logical territory on which he locates the positions he wishes to discuss. This map displays “three roads to open theism.” We think that Tuggy’s roadmap is most perspicuously read as follows.

The three roads result from a series of forks, with the direction taken at each fork determined by the answer given to a certain yes-no question. The first question is,

Does God know future contingents?

The answer to this question determines whether one is heading in the direction of open theism to begin with. If this question is answered in the affirmative, the traveler is not an open theist; if in the negative, he is an open theist. [3] Tuggy’s interest is in mapping the further route of someone who opts for open theism at this first fork. (The traditional theist, who answers this question with a yes, may also face a complex road ahead, but charting it isn’t part of Tuggy’s project in this paper.)

But why wouldn’t a presumptively omniscient deity know future contingents? There appear to be two main options here: either there are no future contingent truths for God to know, or there are future contingent truths but God (for one reason or another) doesn’t know them. The next question, then, is,

Are there any future contingent truths?

The answer to this question, following a negative answer to the question whether God knows future contingents, appears to determine whether the God of open theism can qualify as omniscient, at least in any straightforward sense. An affirmative answer to this second question entails that he is not omniscient, since there will then be truths (namely, all the truths about the contingent future) that God does not know. Tuggy calls this the “narrow road” to open theism, since few open theists endorse it. [4]

Here the road branches again. If there are no future contingent truths, this may be either (i) because all future contingent statements are false, or (ii) because they have no truth-value at all. Those who eschew the narrow road must therefore answer this question:

Are future contingent statements then false?

An affirmative answer allows one to accept, while a negative answer requires one to reject, the Principle of Bivalence, according to which every proposition has either the truth-value True or the truth-value False. The affirmative answer is tempting because it saves one the trouble of contesting the widely accepted Principle of Bivalence with respect to future contingent statements. People in a hurry to get to open theism might veer onto this “short cut,” as Tuggy terms it. This is the route elected by Rhoda et al. The negative answer, committing one to the rejection of Bivalence with respect to future contingent statements, is Tuggy’s wide road.

Tuggy’s paper is a defense of the wide road, not only against fellow open theists who opt for the narrow road or the short cut, but also, more importantly, against classical theists who never got on the road to open theism in the first place because they answered the question, “Does God know future contingents?” in the affirmative. Since we have no stake in the intramural debate among open theists, we shall ignore Tuggy’s critique of the short cut to open theism, leaving it to Rhoda et al. to resist, if they can, the force of his criticism [5]

Tuggy’s principal strategy in the debate with classical theists is to present a positive case on behalf of the wide road, noting intuitions about future contingents that it allegedly satisfies and addressing worries that have been raised against it. Rhoda et al. take a similar approach on behalf of the “short cut.” We shall examine both of their positive cases in subsequent sections of this paper. But first, we need to remind ourselves that there is a negative case as well, and it contributes as much as any positive case to explaining the turn toward open theism.

Why would an otherwise orthodox Christian philosopher come to deny that God knows future contingents? The answer, of course, is that there is a famous argument to the effect that divine foreknowledge is incompatible with future contingents, and hence with robust free agency (assuming that this requires contingency); preserving free agency therefore requires abandoning divine foreknowledge. Let’s call this argument for the incompatibility of free agency and divine foreknowledge simply (and unimaginatively) "The Argument". [6] The papers by Tuggy and Rhoda et al. do not directly address The Argument, but they do presuppose its cogency; after all, hardly anyone would be traveling down any of the three roads toward open theism if The Argument were regarded as unsound [7] We shall also avoid a direct engagement with The Argument, about which so much has already been written. But it is the elephant in the room, and its presence must be acknowledged. We shall confine ourselves to just a couple of points.

First, The Argument is strongly counterintuitive. Mere foreknowledge—in contrast, say, to causal determinism, or to a sci-fi scenario in which we’re controlled by Martians via tiny chips implanted in our brains—just does not seem like the sort of thing which, when added to an action that otherwise satisfies one’s favorite conditions for free agency, could really render that action unfree. For this reason, we believe that an unbiased inquirer would be well within his epistemic rights in regarding The Argument as setting forth a philosophical puzzle awaiting a solution rather than a serious brief on behalf of the incompatibility of divine foreknowledge and human freedom [8]

Second, once all its hidden assumptions are identified, The Argument turns out to be quite complex. There are many points at which it could go off the rails. We have our own favorite ways of rebutting The Argument, and in fact disagree about which way is best; but there’s an embarrassment of riches here for The Argument’s critics. [9] Open theists have tried to imbue The Argument with an aura of impregnability so that nipping it in the bud by denying the problematic foreknowledge in the first place will seem the only viable strategy for preserving human freedom. Anyone coming to this issue unfamiliar with the extensive literature on The Argument might assume that this represents the consensus of the philosophical community and infer that the traditional position on foreknowledge bears the burden of proof in the contest with open theism. But anyone who is familiar with the literature will recognize this as a fundamental misreading of the dialectical situation. [10]

In sum, The Argument is intuitively dubious, and there are many junctures at which it can and has been doubted. It is important to remind the reader that there is a “road not taken,” and it avoids all the difficulties besetting the road(s) to open theism.

Tuggy thinks The Argument’s role is exaggerated, for the following reason. The Argument’s challenge to divine foreknowledge is based on a complex argument invoking robust free will. But there is also a simple argument against divine foreknowledge based on the denial of Bivalence with respect to future contingent statements: if some future contingent statements are neither true nor false, there will be corresponding gaps in God’s foreknowledge, which must again be less than exhaustive. Tuggy prefers this latter argument. (One is tempted to call this Tuggy’s own “short cut”!) Tuggy claims, on behalf of this argument, that the denial of Bivalence with respect to future contingent statements is “strongly rooted in common sense” and “reflects the way that nearly all of us think . . . before committing to some theory.” [11] Here nothing more is needed to motivate the wide road than untutored common sense. This claim seems very dubious to us. Indeed, Tuggy himself, on the very next page, recognizes “that common sense sanctions the belief that we all face a unique future, which could in principle be ‘viewed’ by God or even a psychic.” [12] Such an admission is flatly incompatible with his previous claim. Equally puzzling is Tuggy’s assertion that the statement that some propositions about the future are presently neither true nor false is less “controversial and unilluminating” than the statement that humans have libertarian free will[13] After all, Tuggy and other wide-roaders don’t maintain that it’s the sheer futurity of future events that renders future contingent statements neither true nor false, but their contingency; if there were no future contingents, all propositions about the future would be presently either true or false. For Tuggy, then, some propositions about the future are presently neither true nor false only because humans have libertarian free will, quantum mechanics is indeterministic, and so on—that is, because we live in this kind of world rather than some other kind of world. To the extent that our living in this kind of world is “controversial and unilluminating,” how can something (the denial of Bivalence) that is explanatorily dependent on our living in this kind of world be less “controversial and unilluminating” than what it’s dependent on? Tuggy’s short cut represents a false economy.

As we’ve noted, neither Tuggy nor Rhoda et al. press the negative case for open theism, based on The Argument. Perhaps they think that that particular debate has already been won by their side, or that there is little more they can add to it, or that it’s of limited effectiveness in moving others—for example, people who think that the openist critique of classical foreknowledge has some force but who believe that open theism is even worse—in the direction of open theism. But whatever reason the authors might have for neglecting the negative case grounded in The Argument, it’s the positive case that they pursue, and it’s to their positive case that we now turn, beginning with their understanding of the future.

Open Theism and Branching Models of the Future

It’s striking that in an article devoted to elucidating “the Nature of the Future,” Rhoda et al. never define or explicate the key term “the future.” Indeed, Rhoda et al.’s characterization of the two views about the future which are the focus of their attention is so confused that it’s difficult even to know where to begin in one’s commentary. We may as well begin with the very first sentence of their abstract: on the view they reject, which they call the settled future view (SFV), “the future is settled in the sense that it is exhaustively and truly describable in terms of what either will or will not obtain.” [14] By contrast, on their preferred view, which they call the open future view (OFV), “the future is open in the sense that a complete, true description of it must include reference to what might and might not obtain.” [15]

Immediately one is puzzled because these two ways of describing the future do not seem to be mutually exclusive. To say that the future is truly describable in terms of what either will or will not be seems to be an affirmation that according to SFV the Principle of Bivalence holds with respect to future-tense statements—otherwise, why include “will not be” in the characterization? But Rhoda et al. will later themselves affirm the Principle of Bivalence with respect to such statements [16] So there is no point of contrast there.

What about the claim that on SFV the future is exhaustively so describable? This seems to be the affirmation that there are no truth-value gaps among future-tense statements, again a position to which Rhoda et al. (in contrast to Tuggy) themselves adhere, given their commitment to Bivalence. On the other hand, if this claim is meant to affirm that according to SFV only de facto statements about events which will occur are true, then partisans of the so-called settled view are not at all committed to it. There is, for example, the moral dimension of events to be considered: certain events ought or ought not to occur. The execution of an innocent man will occur tomorrow, but it ought not to. An exhaustive description of the future must include such prescriptive truths. Or consider the modality of events which will occur. Some events which will occur may be causally necessary, whereas others will occur contingently. Though the latter will in fact occur, they will not occur necessarily and so could fail to happen. An exhaustive description of the future must also include such modal truths. But then once again any contrast with the so-called open view evaporates. For although “might” is a terminus technicus in counterfactual semantics, Rhoda et al. use the word in this context merely to indicate causal contingency. [17] Ironically, then, we may hold that the future is both “settled” and “open”; there seems to be no contrast between the two views.

But Rhoda et al. go on to claim that if the future is exhaustively settled, it “cannot be changed,” whereas on the open view the future “can . . . change as matters which are open become settled.” [18]It’s unclear what is being claimed here. At one level it is a familiar analytic truth that the future cannot be changed. In this sense to change the future would be to bring it about that an event which will occur will not occur, which is logically absurd. This analytic truth is independent of so-called settled or open views of the future. At another level, one can “change” the future in that future contingents can fail to occur and one can act in such a way as to prevent their occurrence. Again, this sense of changing the future is common to both views. These are familiar points which need not be elaborated.

So in what sense is the future changeable on one view and not on the other? Rhoda et al. provide a clue to their meaning when they say that on the standard “settled” view, "the set of truths about the future is fixed and unchangeable," in contrast to their view, according to which, as we have seen, the future can change “as matters which are open become settled.” [19] The idea, we take it, is that on the “open” view, since the only future-tense statements that are true are those describing events which are causally determined to occur, then as causally determinative conditions for some event become actual, statements about that event switch truth values, in Rhoda et al.’s view, from false to true. Future events themselves do not change, since, given their assumption of presentism, future events do not exist. Rather what changes is the truth values presently possessed by future-tense statements. In this Pickwickian sense, the future changes. By contrast on the standard SFV view, we’re told, the set of future-tense truths is fixed and unchangeable.

Now at one level, waiving set-theoretical paradoxes, [20] it is trivially true that the set of future-tense truths is fixed and unchangeable, since sets have their members essentially. On the “open” view, neither does the set of future-tense truths change. Rather at different times different sets of future-tense statements are true, in the sense that all of a given set’s members are true. But then it’s evident that this is also the case on the standard view. At different times there will be different sets of true future-tense statements and a unique set at every time. So on SFV, the future also changes in the Pickwickian sense. So the contrast between the standard view and the open view lies not in the supposed changeability of the future, but in which future-tense statements are true or false. On the standard view there are among all true future-tense statements future contingent statements, whereas on the “open” view there are no true future contingent statements. The latter are all of them either truth-valueless (Tuggy) or false (Rhoda et al.).

Curiously, then, on Rhoda et al.’s view the future is, in fact, completely settled “semantically,” as they put it. Whereas on Tuggy’s view future-contingent propositions represent truth-value gaps, on Rhoda et al.’s view there is nothing left to be settled, no gaps at all to be filled, for, in accord with the Principle of Bivalence, future contingent propositions are uniformly false. The future no more changes on the “open” view than on the standard view, for in both cases the change consists wholly in the truth-values presently possessed by future-tense statements. The whole difference between the views lies simply in which statements are presently true. The distinctive thesis of the openness position as defended by Rhoda et al. is that future-tense statements change their present truth value, not only from true to false, but from false to true. All the talk contrasting openness and settledness turns out to be misleading rhetoric.

Rhoda et al. compound the confusion by their equivocal interpretation of branching diagrams of the future. [21] They conflate two quite different interpretations of such diagrams: as representations of the ontology of space-time events and as representations of the causal modality of such events. They introduce such diagrams as depicting “a complete sequence of events stretching all the way back and all the way forward” which is the history of the actual world, along with other causally possible future histories branching off.

Diagram of possible futures showing one that will happen, and others that might happen, but will not.

Already confusion is evident. If the diagram exhibits real events, then the diagram is a futile attempt to represent at once both a tenseless and a tensed perspective on the world. If the diagram is a tenseless representation of temporal moments or events, then there should be no present moment designated and so no branches. If the diagram is a tensed representation, then there should be no solid line representing the sequence of future events, since on presentism there are no such events. As it is, the diagram represents an incoherence, not the “settled” view of the future.

The confusion is augmented by their next diagram, meant to illustrate the open future view.

Diagram of the Open Future View, showing futures that might or might not happen.

The diagram appears to be tensed, for a unique present is denominated and there is no sequence of future events. But then why is the past depicted as a solid line? The diagram depicts, not presentism, but what Rhoda et al. later call the “growing universe” view, [22] which they say they will ignore. In any case, the absence in the diagram of a solid line later than the present in no way illustrates either the failure of Bivalence for future contingent propositions or the falsity of such propositions, for the diagram does not depict the truth status of propositions at a time, but the ontology of events in time.

Rhoda et al. then begin to construe the diagram as a representation of the causal modal status of events. If an event occurs on all branches, it is causally determined; if it occurs on none, it is causally impossible; if it occurs on some but not all, it is causally contingent. But if the diagram represents the modal status of events, why is there a single line from the past through the present? If there have been free decisions in the past or if quantum indeterminacy is ontic, then the past should be branching, too. The diagram should be a thicket, not a tree. Past events may now be determinate without being (causally) determined. The mere passage of time does not remove the causal indeterminacy of an event. Lest Rhoda et al. insist that the actuality of the past is incompatible with its causal indeterminacy, then we should remind them, as Adolf Grünbaum argued forcefully long ago in a classic paper, that the actuality of the future on the B-Theory of time is in no way incompatible with the quantum indeterminacy of future events. [23]

Rhoda et al. might rejoin that on presentism backward causation is impossible, so that the diagram accurately depicts at least the causal closedness of the past as opposed to the future. The problem is that causal closedness/openness is not the same as causal determinacy/indeterminacy. Events which lie on every future branch are causally determined, but they are still open as of the present to causal influences. If there were retrocausation, say, via tachyons, then even causally determined past events would still be open to causal influence. In any case, interpreting the diagram as a representation of which events are, as of the present, open to causal influence does nothing to suggest that there are no true future contingent propositions.

All of Rhoda et al.’s confusions come home to roost in their summary:

Importantly, if the OFV is correct, then the future can and does change. When time’s advance brings us to a node on the tree of causally possible futures, a decision point is reached at which only one of the branches stemming from that node can be taken. When the decision is made, the other branches are ‘pruned off,’ as it were, and fall out of the realm of causal possibility. Thus, the geometry of the future changes through branch attrition. A true might and might not proposition becomes false and a false will or will not proposition becomes true whenever causal possibilities are foreclosed such that what was causally contingent at one point in time becomes either causally necessary or causally impossible at a later point. [24]

Here we see their confusion of future events with future tense statements about those events, their conflation of two distinct interpretations of tree diagrams of temporal events, one ontic and the other modal/causal, their incoherent blend of tenseless and tensed representations of reality, their idiosyncratic understanding of “might” and “will,” and their confusion of causal closedness and causal determinacy.

Tuggy, for his part, gives the branching diagram a different interpretation but exhibits a similar confusion of ontology and modality. He begins with ontology, taking his diagram to be “a linear model of time.” [25] It is a representation of time itself, which has the topological and geometrical properties of a line.

Diagram depicting Tuggy's linear model of time.

Immediately, the problem arises that Tuggy’s Fig. 1 also tries to exhibit both a tensed and a tenseless perspective on time, which is incoherent. For the square node in the diagram represents the present, and yet all moments of time are depicted as existent. Tuggy then in Fig. 2 introduces branches to illustrate the openness of the future.

Diagram depicting Tuggy's linear model of time with branches depicting an open future.

A consistent interpretation requires that time itself thus exhibits a branching structure. Tuggy himself will affirm this, later commenting, “In section 4 above I made the point that if one thinks of time as branching in the future direction, one must hold that some claims about the future are when made neither true nor false.” [26]

But Tuggy proceeds to embrace presentism, which subverts the view that time itself has a branching structure. In a footnote Tuggy admits, “As I’m a presentist, I don’t believe that there are any such things; the future and past ‘branch-segments’ in my model aren’t to be thought of as realities.”  [27] The branches seem to represent modalities, not time’s topological structure. Rejecting as “incoherent” the idea that “there are now ‘many incompatible futures’,” Tuggy takes the branching structure to represent “outcomes which are possible given the course of history up till now. The branch-segments beyond the present represent temporally possible futures—not all the logically or even the causally possible ones, but rather, the ones which haven’t been ruled out by what has happened already together with what is now happening.” [28] So Tuggy does not take the modalities depicted on the diagram to be causal, as Rhoda et al. do; rather it is a kind of temporal possibility/necessity which is depicted. In other words, the model aspires to be a diagrammatic representation of what Alfred Freddoso calls “accidental” possibility and necessity. [29]

But then the problem with the diagram becomes immediately apparent: by depicting the past as a single line segment rather than as branching, it precludes there being any accidentally contingent propositions about the past. But all libertarians think that some past events are “soft” facts and that therefore propositions about their occurrence are not at every later time accidentally necessary—for example, the statement that “Maria Bach gave birth to the greatest Baroque composer,” which could not have been accidentally necessary until the Baroque age had come to an end. Such events fail to be represented anywhere on the diagram. Some theists hold that among past events there are events like God’s believing that some future contingent will transpire, a prophet’s predicting that some future contingent event will take place, and God’s promising to do some action in the future, and that propositions about such events’ having occurred are not, relative to the node of the first fork of the tree diagram, accidentally necessary. So events such as these also fail to be represented anywhere on the diagram.

Tuggy goes on to claim that some interesting things “follow from this picture.” [30] Tuggy must mean that if the diagram accurately depicts reality, then some interesting conclusions follow. But then we need some arguments, such as Rhoda et al. have sought to give, for thinking that the picture does depict reality accurately. Since many thinkers will find the diagram to be a misrepresentation or, at best, an incomplete representation of the world, it is a matter of indifference what follows from it, unless some arguments can be given for its veridicality. Unfortunately, Tuggy does little more than make vague gestures toward an argument, gestures that basically point toward Rhoda et al.’s semantic and metaphysical arguments, to which we shall turn in a moment. [31]

Tuggy then reverts to speaking of the branching diagram as a model of time itself, rather than of temporal modalities: “on the branching model of time there is now no future—no complete future world-segment or branch which is now such that it will be." [32] Taken as serious metaphysics, this is a view of time which takes the branches to be literal space-time manifolds which are pruned off as time passes. This view, which has been defended by Storrs McCall, is, as Tuggy notes, arguably incoherent. [33] It is in any case bizarre and has not commended itself to many. On presentism, which all our interlocutors want to affirm, there just are no branches later than the present, if we take the branches to represent time or event sequences. Rather the tree model is plausibly construed as a pictorial representation of modalities, either causal (Rhoda et al.) or temporal (Tuggy). [34]

In sum, the branching diagram is an attempt to depict, not the structure of time itself, but the temporal modalities of propositions at a given time. But in that case, simply to assume that the diagram resembles a tree is to beg the question against certain classical theists. For it is merely to assume that there are no true temporally contingent past-tense statements to the effect that God foreknew some future contingent. Both Rhoda et al. and Tuggy’s use of branching tree diagrams to illustrate and support their view of the future is thus fundamentally confused.

The Semantic Argument

In addition to presenting a branching model of time, which they believe will appeal to the uncommitted reader but which we’ve argued to be seriously confused, Rhoda et al. present two arguments for the OFV (open future view). More specifically, they give two arguments for what they call “the incompatibility thesis, which says that future contingency is incompatible with a settled future” and hence unavailable to divine foreknowledge. The OFV is alleged to follow from the incompatibility thesis (or IT) in conjunction with “the contingency thesis, which says that there are future contingents. [35] Since their audience, like Tuggy’s, is restricted to those who already accept the contingency thesis, it’s the IT that commands their attention. We look at their so-called “semantic” argument for IT in this section and their “metaphysical” argument in the next.

The semantic argument concerns the causal force presupposed by the predictive use of the word ‘will’—e.g., in the sentence, “The Dean will attend tomorrow’s budget meeting.” Rhoda et al. consider two main options here. What they call the Peircean option “takes the causal force of will to be maximal. To predict that something will happen, in this sense, is to say that it causally must happen.” [36] So Peirceans, who regard the future as causally open, must also treat it as semantically open; that is, they must deny that, “[f]or any possible state of affairs S and any future time t, it must be and always has been true either that S will obtain at t or that S will not obtain at t.” [37] What they call the Ockhamist option, on the other hand, “takes will to have no causal force at all. To predict that something will happen, in this sense, is just to say that it does happen in the future, nothing more.” [38] This allows Ockhamists, who agree with Peirceans in regarding the future as causally open, to treat it as semantically settled, i.e., such that it “always has been true either that S will obtain at t or that S will not obtain at t.” The authors’ contention is that predictive 'will' statements should be assigned a Peircean rather than Ockhamist meaning, and that this settles the controversy in favor of open theism. [39]

To this end, the authors set out “to show that either the Ockhamist or the Peircean position fits more naturally with our colloquial predictive usage of ‘will.’” [40] By this standard, however, it is patently obvious that ‘will’ can express not only a deterministic relation but also, as the authors themselves admit, “a range of indeterministic relations that are compatible with things turning out otherwise, i.e., where the probability of something’s occurring is understood to be less than one but greater than zero.” [41] If the standard is colloquial usage, colloquial usage allows for a broad spectrum of relations, and the Peircean position tolerates only the causally maximal end of the spectrum, it would seem that Peirceanism cannot even get out of the starting gate: there is simply no contest between it and Ockhamism. But then we get this: “While colloquial speech is comfortable with a flexible usage of ‘will,’ relying on context to make clear what kind of force the term is intended to bear on a given occasion, for philosophical purposes we need something more precise—a regimented usage that fixes the causal dimension—so that we can develop a rigorous tense logic.” [42] So much, it would seem, for colloquial usage!

Developing a “rigorous tense logic” which “fixes the causal dimension” may be an edifying exercise for its own sake, but it won’t advance the authors’ larger argument for open theism unless it applies to all future contingent propositions, and does so in such a way that none is true. Now if we adopt a Peircean tense logic, to say that something will happen is to assign it a probability of 1.0; if that something is in fact a future contingent, what was said is false—hence the authors’ affection for the Peircean position. But on what grounds could all propositions about the future be treated in this Procrustean way, since the authors themselves concede that colloquial predictive speech tolerates a wide range of probabilities?

The key move for Rhoda et al. is the appeal to rational assertibility. When determining the meaning of an utterance, “[t]he principle of charity says that a person’s claims ought to be interpreted, if the semantic flexibility of his words and the context allow, in a manner that preserves the rational assertibility of those claims.” Applying this canon to the predictive use of ‘will’, the “degree of causal force we take a future-tense statement to carry depends on what we think the speaker could have reasonably asserted at the time he made the claim.” [43] Rhoda et al. believe they know what that degree of causal force is:

to genuinely assert at u that “S will obtain at t” is to posit its being the case at u that S’s obtaining at t is at least probable. But since we’re looking for a regimented philosophical usage of will that fixes the causal dimension, we have to settle on a particular probability. . . . The Peircean proposal, which takes will to have determinative causal force (probability = 1.0), seems to be the most natural philosophical regimentation of the term’s colloquial usage. After all, it makes more sense to fix the causal force of the unqualified prediction that something will happen at a probability of 1.0 and to use qualifying words like “probably” when lesser causal force is intended, than it does to fix the causal force of will at, say, 0.8, which would then require qualification in both directions. [44]

So despite the apparent diversity of contexts in which people make predictive statements and the wide range of causal commitments exhibited in colloquial speech, which seemed to doom the authors’ Peircean project from the outset, it turns out that it’s the Peircean position, which treats all truths about the future as noncontingent, that fits best with a charitable construal of people’s utterances.

The following are just a sampling of the many problems with this argument against future contingent truths.

1. The argument simply begs the question against the traditional position on divine foreknowledge. Rational assertibility is person-relative; what is rationally assertible for one person may not be rationally assertible for another. This is especially true when the persons in question are as different in their cognitive capacities as God and human beings. But the authors’ dismissal of future contingent truths is based entirely on what they believe to be rationally assertible for human beings; they never so much as entertain the question of what might be rationally assertible for God. If God’s omniscience includes future contingent truths, as the tradition maintains, then such truths are rationally assertible for God; to deny this, on no better grounds than that human beings are not in a position to rationally assert them, simply presupposes the falsity of the traditional doctrine of divine foreknowledge.

2. The authors need to show that all predictive ‘will’ statements should be assigned a Peircean meaning, and rational assertibility is too limited in its application to perform this omnibus task. Rational assertibility helps us figure out the most charitable construal to place on an utterance. But there isn’t always occasion to employ this canon, and when there isn’t, we have no ground to construe putative future contingent propositions as noncontingent. Our own utterances provide one obvious context in which we do not rely on principles of charity to figure out what is being said! But even when rational assertibility is properly restricted to parsing the assertions of third parties, we don’t employ it when the person’s meaning is already clear or subject to clarification. Consider a roulette player who asserts, “The ball will land on 20.” Since the odds are 1 to 35 against this outcome, “absent indications that he really believes that the ball is likely to land on 20,” the authors advise, “we should apply the principle of charity and try to find a plausible construal in the context that does not have him claiming something he is not in a position to know or justifiably believe.” [45] So suppose we question him about his assertion. “I just know,” he replies. At some point we have to take this person at his word. There is no opening here for invoking rational assertibility.

3. The best that Rhoda et al. could achieve, even if we discounted the preceding objections, would be a semantics under which predictive ‘will’ statements were assigned a sufficiently high probability-value—sufficiently high, by the authors’ lights, to make them rationally assertible. That would still leave unexplained the egregious leap to a maximal causal force of 1.0. One consequence of this move, made in the interests of a “rigorous tense logic,” is that many will-statements that would ordinarily be regarded as true will instead turn out false. Indeed, since the Peircean semantics holds that “it is strictly true that something will happen if and only if it is causally determined that it happen,” [46] a statement like “An indeterminate quantum phase transition will occur” is not just false but logically incoherent, like “John is a married bachelor.” It is ironic, to say the least, that rational assertibility—a principle of hermeneutical charity—yields a semantics under which certain statements are more likely to end up false.

4. As a canon of interpretation, rational assertibility can presuppose only that people assert propositions they (rationally) believe to be more probable than not, regardless of their actual probability. So even if we granted the authors’ astonishing contention that rational assertions should be assigned a probability of 1.0, there would still be circumstances in which what are in fact future contingent propositions will be rationally asserted. Having rigged the roulette wheel, our gambler may rationally believe that the ball’s landing on 20 is not only probable but guaranteed. His prediction passes the rational assertibility test. But if a freak martini spill causes the gizmo rigging the wheel to short out, then if the ball still lands on 20, as it might, what the gambler asserted was a true future contingent. It’s only by confusing the epistemic with the ontological that the authors could overlook this obvious problem with their thesis. The gambler’s belief that the ball will land on 20 is one belief; his belief that the roulette wheel is rigged and that the ball must land on 20 is another. The latter is his reason for the former, but these are distinct beliefs, one of them true and the other false. The authors simply conflate the conditions under which it would be rational to assert a proposition with the meaning of the proposition.

5. Rhoda et al. insist that their view can accommodate the fact that some aspects of the future are settled and that some statements about the future are therefore true. Presumably the statement, “The sun will rise tomorrow,” uttered yesterday, would be a paradigmatic example: if this statement can’t lay claim to truth, it’s unclear how there could be any truths about future events (as opposed to, e.g., 2+2’s equaling 4 tomorrow) on the Peircean semantics. But if God exists, then all bets (including causally conclusive bets) are off. Since God is free, then barring limitations (e.g., promises) he has imposed on himself, nothing about the future is causally settled, for God could annihilate the world tomorrow. So there won’t be any true statements about the future. This makes havoc of their claim to be providing the most plausible interpretation of colloquial usage, since such usage is filled with claims about the future.

We could add further objections, but the ones just surveyed are sufficient to show the semantic argument to be an unqualified failure.

The Metaphysical Argument

In section IV of their article, Rhoda et al. present a metaphysical argument for the incompatibility thesis (IT)—“that future contingency is incompatible with a settled future.” They claim that IT follows from the conjunction of the correspondence theory of truth and an A-Theory of time. In other words, their claim is that the correspondence theory of truth and an A-Theory of time together entail that there are no true future contingent propositions.

In order to help us understand the metaphysical argument in support of this bold assertion, Rhoda et al. provide brief characterizations of the correspondence theory of truth and A-Theories of time. Unfortunately, they mischaracterize both of these in ways that vitiate their argument.

“According to the correspondence theory,” they tell us, “a proposition is true if and only if the state of affairs it posits obtains.” [47] This characterization of the correspondence theory is acceptable so long as we do not press it as a statement of serious metaphysics. There is nothing about the correspondence theory that commits us ontologically to propositions or states of affairs (whatever those might be). Unfortunately, Rhoda et al. are not content to rest with their initial characterization of the correspondence theory. They supplement the simple theory with controversial addenda which, as we shall see, play a crucial role in their argument. For example, they give a quite different characterization of correspondence theory when they assert that a denial of correspondence is “a rejection of the idea that true propositions need to be grounded in reality.” [48] It is, however, no part of the correspondence theory of truth that true propositions need to be grounded in reality. That is the theory of truth-makers, a controversial addendum to correspondence theory that has been defended by a minority of recent philosophers. [49] That truth-maker theory has surreptitiously crept into the discussion is evident from the idioms of truth-maker theory that permeate Rhoda et al.’s exposition: they speak of a proposition’s being true in virtue of what is now the case, of what is required to make a proposition true, of propositions’ being grounded in present facts, and so on. [50] Not only so, but in holding that true future contingent propositions need to have truth-makers, they seem to be assuming truth-maker maximalism, an even mere controversial doctrine defended by a minority of truth-maker theorists to the effect that there are truth-makers for all true propositions. As we shall see, Rhoda et al.’s metaphysical argument depends crucially on truth-maker assumptions. Therefore, their mischaracterizations of the correspondence theory will prove compromising to their basic argument.

With regard to Rhoda et al.’s characterization of the A- and B-Theories of time, mischaracterization also takes place, howbeit of a less crucial sort, which makes their exposition merely sloppy. [51] But it is noteworthy how the idioms of truth-maker theory again creep into the discussion. [52]

The intrusion of truth-maker assumptions into their discussion of theories of time becomes serious when Rhoda et al., noting that on presentism there are no non-present states of affairs available to ground the present truth of true propositions, ask, “How then can propositions about the past or future be true?” [53] The tacit assumption here is that such propositions require truth-makers, which, as we say, is no part of the correspondence theory of truth. Hence, it is simply false that “According to the presentist, they are true in virtue of the present obtaining of a tensed state of affairs.” [54]The presentist may say such a thing if he cares to, but he is no more committed to truth-maker theory than the B-Theorist—which is not at all. Truth-maker theory is a thesis which is not a necessary condition of one’s theory of time.

We come, then, to their metaphysical argument for IT. The argument has two stages. The first stage basically reiterates Rhoda et al.’s discussion of presentism:

1. A proposition is true iff the state of affairs it posits obtains (correspondence

theory of truth).

2. No non-present states of affairs obtain (presentism).

3. Therefore, a proposition is true iff the state of affairs it posits obtains now.

4. Therefore, if there are true [contingent] propositions about the future, they must be true

in virtue of the present obtaining of some future-tense state of affairs.

It is evident that (4) does not validly follow from the premises. For (4) presupposes truth-maker theory, which is not entailed by (1).

Curiously, Rhoda et al. illustrate (4) by stating, “Thus, < A sea battle will occur tomorrow > is true now if and only if a sea battle’s going to occur tomorrow now obtains.” [55] This correctly illustrates what follows from correspondence theory as they have formulated it, for it states merely the truth condition of the relevant proposition, not its alleged truth-maker. Rhoda et al. confuse truth conditions and truth-makers throughout their article, beginning with their exposition of the “Truth Conditions Argument,” according to which the sentences “It will rain tomorrow” uttered on Monday and “It rained yesterday” uttered on Wednesday have, in their words, “exactly the same truth conditions, namely, rain on Tuesday.” [56] Rain on Tuesday is not a truth-condition, but a concrete event or entity which a truth-maker theorist might call upon to serve as the truth-maker of any number of propositions. Rain falls from the sky and waters the earth; truth conditions do neither. Similarly, that a sea battle’s going to occur tomorrow now obtains serves as the truth condition of the relevant proposition, whether or not it has a truthmaker.

The only caveat to be made here is that “going to occur” is a circumlocution forced upon us by the absence in English of any gerundial form of the future-tense verb. While we can speak of a sea battle’s having occurred yesterday, we cannot intelligibly speak of a sea battle’s willing occur tomorrow. So we have to advert to “going to occur tomorrow” as a synonym. This is potentially misleading, since some philosophers of time use “is going to” as a terminus technicus for present conditions’ being causally sufficient for some future event and thus emphatically not synonymous with the future-tense. One must take care lest the stated truth condition for a sea battle will occur tomorrow be taken to imply that the battle is now determined by present causal conditions. [57]

In summary, it is open to the correspondence theorist simply to eschew truth-maker theory and to hold that while adequate truth-conditions for true future contingent propositions can be stated, there just are no truth makers of such propositions. [58] Not only is such a position consistent with a correspondence theory of truth, but, moreover, Rhoda et al. offer no criticisms of such a position.

The second stage of Rhoda et al.’s argument attempts to show that there are no true future contingent propositions. It seems to go like this:

5. If a proposition about the future is now true, then it is true in virtue of what is

now the case.

6. What is now the case must somehow bear upon what will be the case.

7. The present bears upon the future in the manner of a cause upon its effect.

8. Therefore, future-tense states of affairs obtain only insofar as the future is

present in its causes.

This second stage of the argument is unfortunately even more loosely formulated than the first.

Premise (5) seems to summarize stage 1 and presupposes truth-maker theory—indeed, a particularly crude version thereof, inasmuch as Rhoda et al. want to know what the obtaining of a future-tense state of affairs “could . . . possibly amount to in concrete terms.” [59] “How,” they wonder, “is reality different because some future-tense state of affairs obtains from what it would have been had that state of affairs not obtained?” [60] At one level such a question is easy to answer: some sentence or proposition has the property truth inhering in it, God is not wondering what will happen tomorrow, accurate prophecies may be given of future events, and so on. But obviously, these are not the sort of differences, real though they may be, that Rhoda et al. are demanding. They seem to think that the future-tense state of affairs must be itself some sort of concrete, detectable reality. But such an assumption is manifestly wrong-headed, for manifold kinds of states of affairs may obtain without concrete, detectable differences of that sort. Think of ethical states of affairs, for example, such as its being wrong to torture a child for fun. That state of affairs obtains whether there even are children or not and whether any that exist ever are tortured. Or think of mathematical states of affairs involving inaccessible cardinals, which are so large they do not correspond to any concrete realities. The idea that truth-makers must be or involve concrete, detectable entities is clearly false (even if we assume that all truths have truthmakers). So if the classical theist wants to embrace truth-maker theory in addition to the correspondence theory, and if, moreover, he holds to truth-maker maximalism or has some other reason for thinking future contingent truths must have truth makers, then there is no reason he may not appeal to tensed states of affairs which presently obtain as his truth-makers.

Rhoda et al.’s response at this point is to protest that “it begs the question by taking Ockhamism for granted.” [61] This retort shows that Rhoda et al. have lost their way in the argument. It is they who are claiming to prove that the correspondence theory of truth and an A-Theory of time jointly entail that there are no true future contingent propositions. To defeat that claim the Ockhamist need not prove or even assume that Ockhamism is true but merely epistemically possible. The Ockhamist offers an epistemically possible hypothesis on which correspondence, presentism, and future contingent truth are compatible. It is maladroit to accuse the Ockhamist of taking his hypothesis for granted. Rather Rhoda et al. must show the Ockhamist hypothesis (in this case, that the truth-makers of future contingent propositions are presently obtaining future-tense states of affairs) is impossible. Instead, they merely muddy the waters. [62]

In short, the Ockhamist who is willing to go beyond the correspondence theory of truth and affirm truth-maker theory could accept (5), taking the truth-makers of future contingent propositions to be presently obtaining future-tense states of affairs.

Premise (6) comes out of the blue, and no explanation at all is given of what the italicized locution “bear upon” is supposed to mean. When Rhoda et al. ask, “How can present reality bear upon a future that does not yet exist?” [63], they seem to take “bear upon” as roughly synonymous with “influence” or “determine,” a surmise reinforced by their contention that the “obvious answer” to the question is (7). Now it is no part of truth-maker theory that truth-makers exert some sort of influence upon truth-bearers, be these propositions, sentences, or what have you. Nor does truth-maker theory require truth-makers of future-tense statements to influence future states of affairs. But no rational motivation apart from truth-maker theory has been given for (6).

As for (7) only an occasionalist would wish to deny it. But (8) does not follow from (7). No reason has been given for thinking that only causally determined future-tense states of affairs obtain now. In short, the metaphysical argument is little more than misunderstanding and assertion.


Rhoda et al. want all true, affirmative, future tense propositions to have the modal status of necessity; any affirmative, future-tense proposition about a contingent event is therefore false. As we have seen, however, their attempt to justify such a position over against the standard view is predicated on confusion about the interpretation of tree diagrams used to represent the open view future view and on semantic and metaphysical arguments which are defective in various ways, including reliance on crude truth-maker theory and a ham-fisted appeal to “rational assertibility” that is driven by the demands of their position rather than respect for people’s actual linguistic behavior.

Tuggy rejects Rhoda et al.’s approach, rightly noting that there are future tense statements which are explicitly or implicitly committed to, or at least neutral with respect to, the contingency of future events. Tuggy’s “wide road” position is that such statements should be treated as neither true nor false, if the future is indeed now causally open (otherwise they would be false). Unfortunately, Tuggy, while offering a semantics for this position and defending its consistency, provides little argument in its favor or against the classic position which accepts Bivalence. His interpretation of tree diagrams as representative of temporal modalities begs the question against certain classical theists if such diagrams are to be taken as including events like God’s believing some future contingent proposition.

“Wide is the gate and broad the road which leads to ruin, and many there are who enter by it,” the Lord warned the crowd in Matthew 7:13. We believe that the wide road to open theism, and its associated short cut, similarly leads to logical and metaphysical (not to mention theological) ruin.

  • [1]

    Alan R. Rhoda, Gregory A. Boyd, and Thomas G. Belt, “Open Theism, Omniscience, and the Nature of the Future,” Faith and Philosophy 23 (October 2006), pp. 432-59; Dale Tuggy, “Three Roads to Open Theism,” Faith and Philosophy 24 (January 2007), pp. 28-51.

  • [2]

    William Craig is an A-theorist, presentist, and Molinist, who holds that God is in time (since Creation) and endorses an Ockhamist solution to the problem of theological fatalism, which he regards as reducible to logical or future-truth fatalism. David Hunt is tempted by the B-theory and perdurantism; he is an anti-Molinist who holds that God is not in time and rejects the Ockhamist solution to the problem of theological fatalism, which he regards as irreducible to the problem of logical or future-truth fatalism.

  • [3]

    Of course one would have to satisfy some other conditions as well (like being an indeterminist and a theist!). So think of this fork in the road as coming after earlier forks; one doesn’t have access to this one unless one took the “theist” turnoff earlier (and perhaps some others as well).

  • [4]

    William Hasker is Tuggy’s principal representative of the narrow road. Hasker insists that the narrow road allows for divine omniscience, but he has to reconceive ‘omniscience’ in making his case—hence the qualification, “at least in any straightforward sense,” two sentences earlier. See his God, Time, and Knowledge (Ithaca & London: Cornell University Press, 1989), pp. 186-88. Peter Van Inwagen endorses a similar position in “What Does an Omniscient Being Know about the Future?” Oxford Studies in Philosophy of Religion, vol. 1, ed. Jonathan Kvanvig (Oxford: Oxford University Press, 2008), pp. 216-230. Another narrow-roader is Richard Swinburne, Providence and the Problem of Evil (Oxford: Oxford University Press, 2006), pp. 22-26.

  • [5]

    Tuggy’s critique of his fellow openists agrees with ours at certain points, but not where it draws on his radical alternative to the “short cut.” Given the incoherence of his interpretation of the tree model of reality (to be explained below), Tuggy’s attempt to justify the sweeping logical reforms he himself proposes as indigenous to the wide road to open theism—including denial of the Principle of Bivalence, construal of “¬,” “Ú,” and “&” as non-truth-functional connectives (or, at least, as not expressive of certain simple negations, disjunctions, and conjunctions), and even rejection of Tarski’s T-schema for truth—is in vain. Nor does the conjunction of an A-theory of time with causal indeterminism imply the reforms Tuggy proposes, as he seems to think. Tuggy’s breath-taking reforms to classical logic go even beyond intuitionistic logic, which is itself regarded by the vast majority of contemporary logicians as a deviant and messy distraction. He also errs in taking defenders of the Principle of Bivalence to assert the logical equivalence of any true tensed statement and a tenseless version of the statement. This assertion is obviously false, since not every true tensed statement is, like tenseless truths, true at all times: tensed statements typically change truth values over time. The point, rather, is that for any tensed truth one can formulate an analogous tenseless statement which will be always, if ever, true. So, for example, prior to Columbus’ landing in the New World it is true that “In 1492 Columbus lands in the New World,” in which case it is hard to see why the tensed statement “Columbus will land in the New World,” asserted prior to 1492, would not be true. Tuggy’s denial of the omnitemporal truth of tenseless truths is predicated, once more, upon his flawed understanding of the tree model of reality.

  • [6]

    Here is one way to articulate The Argument. Suppose God knew before you were born that you would do A at T (where your doing A at T would otherwise be regarded as paradigmatically free). Necessarily, if God knew before you were born that you would do A at T, then you will do A at T. But it’s no longer possible for God not to know that you will do A at T (given the supposition that he did know this). Therefore it’s no longer possible for you not to do A at T.

  • [7]

    At least no one would do so on philosophical grounds, which are the ones at issue in the two papers under discussion. Of course some open theists have come to their position on scriptural grounds. We think the scriptural case for open theism is also mistaken, and we’ve both addressed it in print, Craig in The Only Wise God, rep. ed. (Eugene, Ore.: Wipf & Stock, 1999), Pt. 1, and Hunt in “What Does God Know? The Problems of Open Theism,” Contending with Christianity’s Critics, eds. Paul Copan and William Lane Craig (Nashville: B&H Publishing, 2009), pp. 265-82. But this debate lies outside our agenda in this paper.

  • [8]

    For a defense of this position, see David P. Hunt, “What Is the Problem of Theological Fatalism?”International Philosophical Quarterly 38 (March 1998), pp. 17-30.

  • [9]

    Craig, following William of Ockham, denies that the “necessity of the past” applies to God’s past beliefs about the future, allowing him to reject The Argument’s transfer of necessity to divinely foreknown actions, while Hunt, following Augustine, accepts the transfer of necessity but denies that it undermines free agency, since divine foreknowledge does not cause or explain foreknown actions. For Craig’s position on The Argument, see his Divine Foreknowledge and Human Freedom: The Coherence of Theism: Omniscience, Studies in Intellectual History 19 (Leiden: E. J. Brill, 1990). Hunt’s response to The Argument may be found in his “On Augustine’s Way Out,” Faith and Philosophy 16 (January 1999), pp. 1-26, reprinted in Freedom, Fatalism, and Foreknowledge, eds. John Martin Fischer and Patrick Todd (Oxford: Oxford University Press, 2012). See also Hunt’s “Freedom, Foreknowledge, and Frankfurt,” in Moral Responsibility and Alternative Possibilities: Essays on the Importance of Alternative Possibilities, eds. David Widerker and Michael McKenna (Burlington, VT: Ashgate Publishing Co., 2003, pp. 159-183).

  • [10]

    An excellent summary of the current state of the debate and a sampling of the many response that have been made to The Argument may be found in Linda Zagzebski’s “Recent Work on Divine Foreknowledge and Free Will,” in Robert Kane, ed., The Oxford Handbook of Free Will, 1st ed. (Oxford: Oxford University Press, 2005).

  • [11]

    Tuggy, p. 31.

  • [12]

    Tuggy, p. 32.

  • [13]

    Tuggy, p. 31.

  • [14]

    Rhoda et al., “Open Theism,” p. 432.

  • [15]


  • [16]

    Ibid., pp. 450-4.

  • [17]

    Ibid., p. 436.

  • [18]

    Ibid., p. 432.

  • [19]

    Ibid., pp. 433, 432.

  • [20]

    There cannot be a set of all future-tense truths, just as there cannot be a set of all truths. One should employ universal quantification to speak of all future-tense truths rather than set theoretical concepts.

  • [21]

    The unnumbered diagrams appear on pp. 434 and 436 of their paper.

  • [22]

    Rhoda et al., “Open Future,” p. 447.

  • [23]

    Adolf Grünbaum, “Is There a Flow of Time or Temporal Becoming?” in Philosophical Problems of Space and Time, 2d ed., Boston Studies in the Philosophy of Science 12 (Dordrecht: D. Reidel, 1973), pp. 314-29.

  • [24]

    Rhoda et al., “Open Theism,” p. 436.

  • [25]

    Dale Tuggy, “Three Roads to Open Theism,” Faith and Philosophy 24 (2007): 31.

  • [26]

    Ibid., p. 37 (our emphasis).

  • [27]

    Ibid., p. 50.

  • [28]

    Ibid., p. 33. Cf. his later remark about past and future line segments of the diagram: “What they represent are events which have been real, and events which will become or might become real” (Ibid., p. 50). Obviously, this is not entirely consistent.

  • [29]

    Alfred J. Freddoso, “Accidental Necessity and Logical Determinism,” Journal of Philosophy 80 (1983): 257-78.

  • [30]

    Tuggy, “Three Roads,” p. 33.

  • [31]

    Cf. his statements “Given the openness of the future . . . , there is presently no fact which could make that statement true or false”; “We hold to the truth-realist intuitions that a true statement fits reality, and that a false statement misfits with reality” (Ibid., p. 34). The latter is merely an affirmation of truth as correspondence; the former appears to sneak in truth-maker theory. When Tuggy says that if an event occurs on some but not all branches, “then as of now the non-modal statement lacks what it takes to be true, and also lacks what it takes to be false” (Ibid.), he gratuitously assumes that what it takes to be true is more than correspondence; what it takes is some special kind of truth-makers. In fairness to Tuggy, we must say that “the main thrust” of his argument is merely that “open theists ought to travel the wide road” rather than other roads to open theism (Ibid., p. 28). We agree wholeheartedly with that advice. But then the question remains why Christian philosophers ought to join them on this perilous path. It is left to Rhoda et al. to do the convincing.

  • [32]

    Tuggy, “Three Roads,” p. 33.

  • [33]

    Storrs McCall, A Model of the Universe, Clarendon Library of Logic and Philosophy (Oxford: Clarendon Press, 1994); for a critique, see William Lane Craig, critical notice of A Model of the Universe, by Storrs McCall, International Philosophical Quarterly 35 (1995): 354-356.

  • [34]

    Strangely, Tuggy attacks the suggestion that the model depicts modalities. “If we assume that there is (timelessly or now) an actual future, then this suggestion makes perfect sense. But this is to affirm the linear model of time; there will be, at any time, exactly one accessible future (though there may be many other logically, causally, and epistemically possible futures)” (Tuggy, “Three Roads,” p. 34). This assertion is bewildering. The linearity of time has to do with its topological structure: it is a one dimensional manifold of points ordered by a betweeness relation. Viewed from a tenseless perspective it looks, well, like a line—there are no branches. In rejecting an interpretation of the branches like McCall’s and yet in endorsing a branching model, Tuggy must be taking the branches to depict modalities. By shunning logical, causal, and epistemic construals, he must be taking the branches to depict temporal modalities, just as he said.

  • [35]

    Rhoda et al., “Open Theism,” p. 432.

  • [36]

    Ibid., p. 439.

  • [37]

    Ibid., p. 433.

  • [38]

    Ibid., p. 439. The authors’ Peircean-Ockhamist distinction comes from Arthur N. Prior, Past, Present, and Future (Oxford: Clarendon Press, 1967), pp. 113-36. We leave it a moot question whether such “Ockhamism” accurately represents the view of either Ockham or his Anhänger.

  • [39]

    Tuggy, by contrast (and, in our view, rightly), allows for future contingent sentences to express both Peircean and Ockhamist propositions, where the latter are regarded by him (this time, in our view, wrongly) as neither true nor false. The fact that Rhoda et al. attempt to reach open theism by bypassing Ockhamist propositions altogether may be one reason Tuggy refers to their road as the “short cut.”

  • [40]

    Ibid., pp. 439-40.

  • [41]


  • [42]

    Rhoda et al., “Open Theism,” p. 439.

  • [43]

    Ibid., p. 442.

  • [44]

    Ibid., p. 443. This is a good point at which to draw attention to the authors’ conflation of probability with causal necessity and contingency. A probability of 1.0 doesn’t imply causal determinacy. Probability has to do with the expectations of a perfectly rational agent, and these expectations may be based on something other than causal determinism. A time traveler, for example, may be certain of the future (it has a probability of 1.0 relative to his background beliefs) despite its causal indeterminacy.

  • [45]

    Rhoda et al., “Open Theism,” p. 443.

  • [46]

    Rhoda et al., “Open Theism,” p. 436.

  • [47]

    Rhoda et al., “Open Theism,” p. 447; cf. p. 446. They stipulate, “In asserting something to be the case, a proposition posits a state of affairs” (Ibid., p. 40).

  • [48]

    Ibid., p. 448.

  • [49]

    See discussion and literature cited in William Lane Craig, “Middle Knowledge, TruthMakers, and the Grounding Objection,” Faith and Philosophy 18 (2001): 337-52.

  • [50]

    Rhoda et al., “Open Theism,” pp. 447-8.

  • [51]

    E.g., their speaking of “direct accessibility” when they really mean simultaneity, their confusing sentences with propositions, their handling of states of affairs sometimes as abstract objects which obtain and sometimes as concrete objects which ground the truth of propositions, and their construing presentism to entail the denial of timeless entities such as God or mathematical objects and, hence, timelessly obtaining states of affairs in addition to presently obtaining states of affairs.

  • [52]

    E.g., on the B-Theory non-present states of affairs are available to ground the present truth of propositions, propositions about the past or future can be true in virtue of the past or future obtaining of a tenseless state of affairs, etc. N.B. that the mere availability of such states on the B-Theory does not imply that the B-Theory is committed to truth-maker theory.

  • [53]

    Rhoda, et. al., “Open Theism,” p. 446.

  • [54]

    Ibid., pp. 446-7.

  • [55]

    Ibid., p. 447 (emphasis in the original).

  • [56]

    Ibid., p. 434.

  • [57]

    In the closing summary of their argument Rhoda et al. take the aforewarned slide from asserting “the present truth of < S will obtain > depends entirely on S’s going to obtain now being the case” to concluding, “ is now true, therefore, if and only if present conditions are in fact sufficient, that is, fully determinative, of the future obtaining of S,” where “sufficient” and “determinative” are taken to mean causally sufficient and causally determinative. But no good reasons have been given for thinking that “S’s going to obtain” describes a state of affairs which is causally sufficient for S.

  • [58]

    For a trenchant critique of truth-maker theory, see Trenton Merricks, Truth and Ontology (Oxford: Oxford University Press, 2007). Merricks takes his denial of truth-maker maximalism to be incompatible with a view of truth as correspondence, but he understands correspondence differently than Rhoda et al.

  • [59]

    Rhoda, “Open Theism,” p. 447.

  • [60]

    Ibid., p. 449.

  • [61]


  • [62]

    For example, they assert, “On a presentist ontology, presently obtaining future-tense facts cannot be grounded in future present-tense facts because there are no future facts” (Rhoda et al., “Open Theism,” p. 449). Since “facts” is being used here in the sense of “states of affairs,” the confused claim is that the truth-makers need themselves to be further grounded. Moreover, the misgiving expressed here seems to take grounding to be a causal relation, which by all accounts it is not. Since the relation between a truth and a truth-maker is not causal, it is not even evident why the Ockhamist could not take states of affairs which will be actual to be truth-makers of future contingent propositions.

  • [63]

    Rhoda et al., “Open Theism,” p. 447.