EUROPEAN JOURNAL FOR PHILOSOPHY OF RELIGION 6/3 (AUTUMN 2014), PP. 25-37 NOT ENOUGH POWERS PETER FORREST University of New England Abstract. In God and Necessity Brian Leftow provides an original explanation of kinds and essences in terms of freely chosen divine powers, which act as (substitutes for) possible worlds. Although I agree that kinds and essences are the result of God's free choice and am impressed by Leftow's scrupulous attention to detail, I shall argue that divine powers fail to do the work that they are meant to do. I shall argue this in three stages. First I provide an alternative explanation of absolute necessity using the good old analytic/synthetic distinction. Then I argue that if we need possible worlds or substitutes for possible worlds to consider counterfactual situations, there are not enough divine powers to provide these worlds (or substitutes). Finally I argue that kinds and essences are indeed dependent on God's choice but in a negative fashion, being the result of divine self-limitation.1 In God and Necessity Brian Leftow begins with a – to me – convincing case that there is a fundamental modality of absolute necessity, and then proposes an explanation of secular necessity. He does this by assuming that a secular necessity is an absolutely necessary secular truth. By absolute necessity Leftow means the necessity relative to which other necessities are characterised. Suppose, for instance, that there are laws of nature that God, in performing miracles, can perhaps break. Let their conjunction be k. Then we may say a proposition p is physically necessary if not-((not-p) and k) is absolutely necessary. By a secular proposition, Leftow means one that is about non-divine concrete entities, those that theists would consider created. It would seem to follow that an explanation of the absolute necessity of secular truths is an explanation of secular necessity. I disagree. For Leftow's examples 1 Many thanks to Einar Duenger Bøhn for his useful comments, especially on my assimilation of absolute non-contingency to analytic non-contingency. 26 PETER FORREST of secular necessity, such as that water is H2O, are absolutely necessary because water, hydrogen and oxygen are natural kinds. The explanatory work is done, I say, by the existence of these kinds, which is not a matter of absolute necessity. That is my first point of disagreement with Leftow, and the topic of Section One. As part of his explanation of absolute necessity, Leftow offers us (substitutes for) absolutely possible worlds, namely the world-powers as he calls them. The idea is that God freely comes to have various powers and what God has the power to do is possible, hence, it is said, the powers explain the possibilities not vice versa. In Section One I provide an alternative explanation of absolute necessity, one that is neutral between theism and atheism. In Section Two I shall argue that if we need possible worlds there are not enough divine powers to act as substitutes for them. That would be a problem even if there were no alternative account of absolute necessity, such as the one I provide in Section One. Finally, in Section Three, I shall sketch an alternative theory of how God brings about kinds and essences. I. ABSOLUTE NECESSITY Near the beginning of the book Leftow provides a convincing case for there being a fundamental modality of necessity no-matter-what (pp. 30-38, my hyphens). I interpret this to mean that those truths that no human being can bracket off, that is suppose false, are absolutely necessary. Hence counterfactual conditionals with antecedents that are impossible-no-matter-what are trivial and usually taken to be vacuously true. To be sure we can reason about such situations, but only formally. For example, Euclid's famous proof that there is no largest prime number begins by inviting us to assume the contrary, multiply all the primes and add one. He then shows that this would be a new prime, which is absurd. In that, formal fashion, we can reason about the impossibleno-matter-what.2 But we are unable to reason more generally about the counterfactual situation in which there is a largest prime. Or if we can it is only because we decide that all such counterfactuals are vacuously true. Likewise, we have no trouble assessing 'If a married bachelor 2 In this paper I shall not argue over which, if any, mathematical truths are true no matter what. My opinion is that the Axiom of Choice is not such, but the existence of an infinity of natural numbers is. 27NOT ENOUGH POWERS gets married he is a husband', but we cannot assess the conditional, 'If a married bachelor gets married he does something wrong', except, perhaps, to say it is vacuously true. We may contrast this with the case of physical necessity. We may coherently suppose that classical rather than quantum mechanics is true and indeed we do make that coherent supposition in many applications of physics. This idea of what may coherently be supposed, or, equivalently I hope, has a negation that may be supposed false, explicates the traditional notion of an analytic truth, and I shall henceforth use the term 'analytic' for 'necessary no-matter-what'.3 Now, the truth that there are thoughts and hence propositions is not itself analytic, nor need it be for the proposed characterization of the analytic to succeed. I mention this because Leftow criticizes the assimilation of absolute necessity to being analytic – an assimilation I do not quite make – partly on the grounds that it makes the necessity of necessary propositions depend on the existence of these propositions (pp. 483-60) which is not itself an analytic truth. This point is made clearer by a consideration of possible worlds. Many of these contain no thoughts, but that does not stop us thinking about them. In that respect they do not differ from black holes. We can reason coherently about them even though they are uninhabitable. So we should ask why absolute necessity is not just being analytic. The answer is because there are analytic truths of the form 'It is (absolutely) non-contingent that p', where p is not itself analytic. Ontological arguments of one sort or another might be taken to establish this for p = 'God exists'. In addition, there are Kripkean necessities of identity such as p = 'Hesperus is Phosphorus' or natural kind truths such as p = 'water is H2O'. And there are essential truths such as 'Hesperus is in fact an inanimate material object, not a goddess'. These last two types of absolutely necessary truths are paradigms of secular necessities. Therefore, I characterize absolute necessity as the narrowest necessity satisfying S5 modal logic that includes all analytic truths and that treats every truth as absolutely possible. Other less narrow necessities are then obtained by considering any set of absolutely possible worlds and any accessibility relation between them. 3 I assume closure under a small number of rules whose truth-preserving character is itself analytic. 28 PETER FORREST Secular propositions are those about concrete entities that do not presuppose theism. Leftow is offering us a theory of the absolute necessity of some secular propositions such as that water is H2O. I say, however, that we do not need a theory of its necessity other than a theory of its truth since it is absolutely non-contingent. Moreover Leftow's explanation of necessity is based on the idea that we do not need to explain why there are no additional worlds so anything that is true at all the posited worlds, or their substitutes the divine powers, is necessarily true. But I fail to see how the mere lack of extra worlds explains anything unless we can explain that lack in turn, but according to Leftow it is just God's free decision and so not explained. The Circularity Objection To define absolute necessity in terms of analytic truths about absolute non-contingency would be circular, but that is not my intention. I have learnt from Leftow that we have this concept of absolute necessity and I then claim that the analytic/synthetic distinction enables us to explain truths about absolute necessity in terms of other truths that are not modalized. To any who would remind me of W. V. O. Quine's paper 'Two Dogmas of Empiricism' my reply is brief, 'I am not an empiricist'. A Dilemma for Leftow I now propose a dilemma. Do we need possible worlds or even substitutes for possible worlds except, perhaps, to characterize necessity as truth at all possible worlds? If not then we may characterize absolute necessity as above and do without the possible worlds. But if we do need them for other purposes such as analyzing counterfactual conditionals then, we need all absolutely possible worlds not just some of them. For anything we may coherently suppose may be the antecedent of a non-vacuous counterfactual conditional. II. AGAINST DIVINE POWERS AS WORLD-SUBSTITUTES I now argue that there are not enough divine powers to act as worldsubstitutes. I do so by providing some objections to Leftow's theory. These objections have more weight in the context of the previous section, where an alternative account is provided of absolute necessity. They are still serious objections even if my reliance on the analytic/synthetic distinction is rejected. For they exhibit some unattractive features of 29NOT ENOUGH POWERS Leftow's account, ones which would be troublesome even if there were no better account available of absolute necessity. Objection One A Version of the Modal Problem of Evil Here is a version of the modal problem of evil, based on that of Theodore Guleserian.4 It uses as a premise the possibility of a world that is at all times gratuitously evil, and so such that an all-powerful all-knowing God would have terminated before any given time, however far in the past.5 Such a possibility is inconsistent with the existence of an essentially good, all-powerful, God. It follows from the premise that there is no essentially all powerful, all knowing and good God that exists necessarily. Leftow rejects the premise, to which I shall return. I would reject the thesis that God is essentially good, holding instead that, like the blessed in Heaven, God is good because God has every reason to be good. But this might seem rather too radical for perfect being theologians, so I now provide an alternative way of resisting the modal argument from evil without denying the premise. I suggest that divine omnipotence is to be adjusted as follows. In place of omnipotence there is the perfection of being able to do anything you desire to do.6 By itself that perfection does not give any powers at all, but combined with divine goodness it ensures very many powers, and acts as a substitute for omnipotence. Making this modification, it turns out that God has no power to create thoroughly evil worlds. This response, however, grants that there are possible worlds that God does not have the power to make actual. My case for the possibility of such gratuitously evil worlds has two premises. The first premise is that there is a possible world w in which similar evils result from the free choice of creatures. The second premise is that whatever a creature can freely bring about, God could cause that creature to bring about in a way that is not free, and hence there is a world w* rather like w in which God does just that.7 4 See Theodore Guleserian, 'God and Possible Worlds: The Modal Problem of Evil', Noûs, 17 (1983), 221-238. 5 Leftow points out (p. 120) that his theory is a way of rejecting such premises without being ad hoc. That does not affect the objection. 6 Just as an omnipotent God lacks the power to cause a creature to act freely in a certain way, I assume the perfection that substitutes for omnipotence would not attribute to God such a power, even if God should desire to exercise it. 7 Clearly, the phrase 'whatever a creature can freely bring about' must not be taken to refer to the creature as the agent or the creature's freedom. 30 PETER FORREST To establish the first premise consider, for instance, a possible world w, in which there have always been inhabited planets on each of which there are humanoids with two by-God-intended first parents, whom we may as well call Adam and Eve. In this world, they always sin by freely eating the forbidden fruit, and the chemicals in the fruit make them sterile. I have it in for them, so I decree that it prevents them from even having sex. They die in some discomfort after leading futile sinful childless lives. Moreover there is no afterlife. I assume that God can create such a world with an infinity of Adams and Eves free to obey or disobey. Rather than establish the second premise in full generality, it suffices to consider again the example of the possible worlds with an infinity of culpable Adams and Eves. God could create a world in which they do not act freely but are predestined to disobey, provided God decides to redeem the world by, among other things, ensuring an afterlife. So for any given time t, there is a possible world w*(t) exactly like the putative world w* up to t, and such that no good God would create. I now ask at what time does w* cease to be possible? The absence of any answer shows that w* is possible. Nor can this conclusion be resisted by supposing an omega moment after the end of ordinary time. For if that is coherent so is the corresponding modification of w in which various Adams and Eves go on making the wrong choices after the end of ordinary time. I conclude that those who want to defend the essential perfection of a necessarily existing God should grant the suggested replacement for omnipotence and hence concede that w* is a world that is possible but God cannot bring about. It might be objected that God is not so niggardly as to create such worlds as w*(t), and so Premise (1) is not secure. If this is just a matter of raising the standard for being creation-worthy then I will adjust the example. Suppose for instance we allow a world in which the Adams and Eves live futile lives by our standards but, themselves having low standards, enjoy themselves immensely eating more and more of the forbidden fruit. I invite readers to consider a scenario in which these low standards are the consequences of their eating the forbidden fruit, because the chemicals in it damage their brains. Because they are by nature fitted for higher things, w* would still not be good enough to create if they were predestined. In further support of my conclusion that divine perfection requires not omnipotence but rather the conjunction of divine goodness with being able to do anything you desire, I note that Leftow's account 31NOT ENOUGH POWERS trivialises divine omnipotence, because the possibilities are limited to the powers God chooses to have. So Leftow already has reason to replace traditional omnipotence by my proposed substitute when listing the divine perfections. Objection Two: The 'It was in God to' modality If God freely chose the divine powers, then in some sense God had the capacity to acquire different powers from the actual ones. So there might have been different world-powers and hence different secular possibilities. But, I say, whatever is possibly possible is possible, so it is possible for God to have had different powers, contrary to the use of divine powers as substitutes for secular possibilities. Leftow anticipates something like this objection, acknowledging Thomas Flint and Michael Rea (p. 253, n.7). His response is that 'it was in God to' would not be an interesting modality. I disagree: to say that it was in God to acquire other powers implies it is consistent with the divine nature to acquire these powers and hence that it is possibly possible to acquire these powers. Leftow claims, however, that prior to God's acquisition of various powers many modal propositions had truth value gaps. Leftow considers the example of a natural kind, zogs, which God could have but did not create. So he would say that the propositions that necessarily all zogs are perky and possibly all zogs are perky both have truth-value gaps, being neither true nor false. On the contrary I submit that given any type of possibility the modality of its not being false that possibly is also a type of possibility that is at least as broad. But absolute possibility is the broadest type, corresponding to the narrowest type of necessity. So bivalence must hold for the absolute possibility: it is either true that possibly p or true that not possibly p. Likewise for any type of possibility, possibly possibly is a type of possibility as least as broad. Hence for absolute possibility both 'Possibly possibly p' and '"Possibly p" has a truth-gap' imply 'Possibly p'. I conclude that it being in God to have zoggenic powers is enough to ensure that zogs are possible, because either it is not true that zogs are impossible or it is possible that zogs are possible and in either case zogs are possible, if we are concerned with absolute possibility. From Leftow's assertion that it was in God to have chosen different powers it now follows that not all secular absolute possibilities correspond to divine powers. 32 PETER FORREST I anticipate the objection that Leftow is not committed to absolute possibility being maximally broad. To that I have three replies. The first is that maximal breadth is implied by his case for absolute modality as that in terms of which other modalities are defined by restriction. The second is that my account of absolute necessity in terms of analytic truths implies that it is maximally broad. The third is that whatever the case for possible worlds it should apply to absolute possibility as I have characterised it. Assuming we need possible worlds or substitutes it follows that there are possible worlds in this broadest sense even if this is not what Leftow has in mind. Hence even if there are enough world-powers to act as substitutes for all Leftow-absolutely-possible worlds there are not enough for all worlds, because we also need Leftowabsolutely-impossible worlds or substitutes for them. Objection Three: Additional Natural Kinds and Individual Essences This objection is similar to the previous one, and as with the previous one Leftow anticipates something like it, considering a William Rowe inspired objection that whatever kinds and individual essences God brought about, God could have produced more. That would be a reductio ad absurdum of divine perfection (pp. 290-298). But it also shows there are possibilities in excess of the divine powers, contrary to Leftow's theory. He argues, however, that the lack of zoggenic power is not a genuine limitation on God's power because zog-production would not be a power God has by nature but one that it was in God to acquire. My response to Leftow's case against zoggenic powers is that (1) God is in time and (2) if it is in God initially to come to have various powers then presumably it is still in God to have additional powers. If we knew more about God we might say that this presumption is overcome, but in the absence of that knowledge there is a high probability that it is in God to go on acquiring additional powers. Leftow has, however, an implicit objection to (2). He says that it is part of the divine nature to be powerful and that requires only that God come to have at least one world-power. So he would say that we do know enough about God to know that quite a limited range of powers would have been enough to satisfy the requirement that God be powerful. But this suffers from the same difficulty as the account of X's being omnipotent as X's having all powers consistent with X's nature. The difficulty is that a being, MacEar, whose nature restricts him to scratching his left ear, would 33NOT ENOUGH POWERS count as omnipotent.8 Likewise Leftow's implicit rejoinder entails that God would count as a powerful being even if the only divine power was to create a world containing nothing more than a single creature with a momentary pleasant experience. Although we cannot create such a world, we can, I join with Leftow in believing, do something much more momentous, choose not to reject God's offer of friendship. So the power to produce the single momentary pleasurable experience is not enough. Nor will it help to require an infinity of divine powers, or even too many to form a set. For the power to create universes with N such momentary experiences for all cardinal numbers N, although impressive in one respect, does not do justice to what is 'in God'. We have no reason, then, to overcome the presumption that it is always in God to acquire additional powers. As for (1), Leftow argues that it is absurd to think of God waiting and then creating new kinds by coming to have new powers. For, he says, whatever reason God had to produce new kinds, God would already have had that reason initially. One response might be that God has much to do and so the divine events themselves form a continuum with God arranging the order in some aesthetic way (hyper-music!). A less extravagant hypothesis is that every moment of divine time has a next moment. In that case, I say God is in ordinal not metric time, and it is not a question of time lapsing but of God's doing something the very next moment. Ordinal Time My third objection to Leftow's theory depends, therefore, on my preference for saying that God is in ordinal not metric time, over both strict divine eternity and God experiencing time as we do. Ordinal time is based on the B series relation; x is before y. I distinguish it from metric time based on the 'D series' relation: w is before x by more than y is before z. The latter is a topic in physics, which supports its unification with the spatial metric in space-time. The former is a topic in metaphysics, although physicists may have something to contribute. One important difference between divine time and our immersion in metric time is that the latter results in the passage of time, which can be explicated as the relation between the metric and the ordinal. Assuming that for 8 I use this example because it is traditional, even though offensive. Apologies to those with the surname 'McEar' and to the severely disabled. 34 PETER FORREST every moment of ordinal time there is a next moment, a successor, then we may consider the quantity of metric time that lapses between one moment of ordinal time and the next. This is the rate of passage of time, and is measured in seconds per next. The plausible doctrine that God is not passively swept along by time, as we are, supports either divine ordinal time or divine eternity. Likewise if God is distinct from, because the creator of, the whole physical world including space-time then God is not in metric time, but might well be in ordinal time. Leftow's theory of absolute necessity is motivated by his adherence to the thesis that everything non-divine, not just concrete entities, depends on God. So ordinal time depends on God. I invite readers to share my intuition that ordinal time is necessarily unending so that when we talk of the end of time we are considering ordinal time after the end of metric time. Combining this intuition with the dependence of ordinal time on God, I reach the conclusion that ordinal time is not a creation and hence depends on God in some other way. The only plausible suggestion is that ordinal time depends on God because it is the divine nature to be in ordinal time, with each divine moment having a successor. This completes the third objection. Leftow might suggest, by way of rejoinder, that the unending nature of ordinal time is just another secular necessity. But this is not a truth that holds just for our universe, like a law of nature. For time is unending, we intuit, even if the universe comes to an end. III. AN ALTERNATIVE THEORY OF KINDS AND ESSENCES Leftow's examples of secular necessities involve individual essences such as 'Spot is a dog' and natural kinds, such as 'Water is H2O'. In Section One, I argued that the absolute necessity of these claims follows from non-modal truths together with analytic truths about absolute noncontingency. So all that is required is a theory of how God ensures there are these essences, not other ones, and these natural kinds, not others. I shall suppose, then, that God is aware of the plenitude of all absolute possibilities characterized in some way that does not yet involve natural kinds or individual essences. Then God acts as a sculptor, chipping away at the possibility-block, knowing the chips only as might-have-beens. The more God sculpts, the more determinate becomes the structure of the still possible, with natural kinds resulting. For example, suppose we 35NOT ENOUGH POWERS have various possible quantities: rest mass, charge, and so on. Initially there is a continuous variation of all these quantities, but by prohibiting any values near but not exactly equal to those of an electron, God brings into existence the natural kind, electrons. Likewise if we consider the continuum of possible dogs and their lives, there is no precise boundary between those that in hindsight we can call Spot-counterparts and Topscounterparts. But by prohibiting all but a fairly narrow range of lives, Spot and Tops are left as distinct possible dogs, that is, individual essences. The same procedure holds for whole universes, which have no clear separation from each other in the original plenitudinous block of absolute possibilities. Our universe is in there as a number of possible ways things might turn out but not yet separated from other ways that are no longer possible. To use an image of Leibniz', it is like a statue before it has been carved. It is there in the block but not distinct from the rest of the marble. Another candidate for secular necessity is that possessed by laws of nature, to which I assimilate some of the more recherché mathematical axioms such as the Axiom of Choice and the Continuum Hypothesis. I also assimilate to the laws some truths known a priori as 'no surface can be uniformly red and green', which Leftow cites as an example of absolute necessity (p. 34). Leftow notes that we can explain the laws in terms of essences (p. 251). Thus we may say that it is essential to being our kind of universe that a certain regularity (that corresponding to the law) holds.9 Given the above account of individual essences, this is a matter of God's clarifying the counterparts by excluding very many possible worlds in which universes rather like ours occur but the regularities do not hold. Clearly this gives room for God either to exclude all exceptions or to permit some exceptions to ensure scope for miracles later on. I prefer the former, but even on the latter, God, by excluding various possible universes, engages in a kenotic self-limitation prior to creation, so we may say that the divine powers are indeed the result of divine choice, but in a negative fashion. Although not previously showing any enthusiasm for the above theory of laws, I have come to appreciate it. For the alternative realist (i.e. anti-Humean) theories seem to imply that the same laws as ours hold in all actual universes. Some such as the Dretske-Tooley-Armstrong theory 9 See John Bigelow, Brian Ellis and Caroline Lierse, 'The World as One of a Kind: Natural Necessity and Laws of Nature', British Journal for the Philosophy of Science, 43 (1992), 371-388. 36 PETER FORREST that laws are relations between universals seem to imply that they hold in all possible universes too.10 (Evan Fales accepts this conclusion.11) But even though the details of divine motivation in creation are hard even to speculate about, it seems plausible to me that God would not be so niggardly as to create either just one universe or just a multiverse comprising many universes with the same fundamental laws. The idea of God-the-sculptor carving away at a block of absolute possibility does not require any ontologically basic possible worlds. For the possible worlds may be thought of as constructs out of possibilities in much the way that a Whiteheadian theory treats points as constructs out of regions.12 Thus the block of possibility is initially endowed just with a point-free topological structure. In addition we do not have to follow Leibniz in thinking of God as actualizing a pre-existing possible world. Instead we may take an act of creation to involve an assignment of cardinal numbers to regions in the possibility-block, with 'possible worlds' being arbitrary assignments, subject to the coherence principle that if region X is part of region Y, X cannot be assigned a greater cardinal than Y. My proposal meets the objections I raised to Leftow's theory. The Modal Argument from Evil can be dealt with using the thesis that God sculpts the plenitudinous possibility-block. The possibilities that would make up a world of gratuitous evil are there, but prior to divine action they are not yet incorporated into a world distinct from other worlds. Either God has the power to carve it but never does, in which case God is omnipotent but not essentially good, or God lacks that power while nonetheless having the power to bring about whatever is desired. But in neither case does the existence of the possibility of the gratuitously evil world refute my theory. The second objection to Leftow's theory clearly fails to apply to my proposal. For the range of absolute possibilities is wholly unconstrained 10 See Fred Dretske, 'Laws of Nature', Philosophy of Science, 44 (1977), 248–68; Michael Tooley, 'The Nature of Laws', Canadian Journal of Philosophy, 7 (1977), 667–98; and David Armstrong, What is a Law of Nature? (Cambridge: Cambridge University Press, 1978). 11 Evan Fales, 'Are Causal Laws Contingent?', in John Bacon, Keith Campbell & Lloyd Reinhardt (eds.), Ontology, Causality and Mind: Essays in Honour of D.M. Armstrong (Cambridge: Cambridge University Press, 1993). 12 For some details see Peter Roeper, 'Region-Based Topology', Journal of Philosophical Logic, 26 (1997), 251-309. See also my The Necessary Structure of the All-pervading Aether: Discrete or Continuous? Simple or Symmetric? (Frankfurt: Ontos, 2012), p. 160, where I summarize the ultrafilter construction of points, discussed in greater detail in 'Mereotopology without Mereology', Journal of Philosophical Logic, 39 (2010), 229-254. 37NOT ENOUGH POWERS in reality and appears constrained to us, only because of the way we think.13 So there is no need for further possibilities other than those God contemplates. As for the last objection I may need to allow that the plenitude of absolute possibilities is neutral between the number of copies of each possibility. As a consequence, when God sculpts the range of possibilities, there is still a copy of the original plenitude that God could work on. So God has the power to create essences and natural kinds again and again. This would be an important qualification to the idea of divine self-limitation. Finally I turn to Leftow's rejection of Deity theories of absolute necessity, namely those that assert the absolute necessity reflects God's nature. He complains that this makes God's existence depend on the truth-makers for necessary truths about creatures (p. 209). I note, therefore, that my proposed alternative to Leftow's theory is not open to this criticism. For the absolute necessities are dependent on (1) the analytic truths, and (2) the natural kinds and individual essences that God brings into being. That requires a realm of absolute possibilities for God to know, prior to carving it into discrete possible worlds. This possibility-block depends on God's nature, to be sure, but it is prior to the existence of individual essences, and can be considered a realm of mathematical possibilities. Leftow concedes that God's nature might determine all logic and pure mathematics (p. 154). I myself would restrict this to analytic truths, and such part of logic and mathematics that is synthetic would be assimilated by me to the realm of natural kinds and essences. But it seems that a deity theory of absolute possibilities prior to the carving into kinds and essences is acceptable. To those who would object that this has a pantheistic flavour with the possibility-block being the divine body, I agree but see no objection. 13 The Kantian account of the synthetic a priori extends the range of such constraints. For this paper it suffices that analytic truths arise from. such constraints. I do not need to discuss what other truths there might be that are similarly the results of constraints on thought.