The Southern Journal of Philosophy (1986) Vol . X X I V , No. 4

CAN THERE BE A

Laura L. Garcia Catholic University of America

SELF-EXPLANATORY BEING?

In the posthumously published The Miracle of Reism,‘ John Mackie argues that it is irrational to believe in the existence of God, where God is understood to be a necessary, omnipotent, omniscient and morally perfect being. Prior to presenting the positive case against God’s existence, Mackie re-examines many of the traditional arguments in favor of theism and provides his own account of where each argument fails. I focus here on just one such critique, Mackie’s refutation of the cosmological argument in its Leibnizian form, where theargument makes use of the principle of sufficient reason. According to Mackie, Leibniz’ proof requires the notion of a being whose essence includes its existence, a notion that is deeply suspect because i t is not clear that a being whose essence includes its existence is evenpossible. As Mackie puts it:

Since it is always a further question whether a concept is instantiated or not, no matter how much i t contains, the existence even of a being whose essence included existence would not be self-explanatory; there might have failed to be any such thing. This ‘might’ expresses a t least a conceptual possibility: if it is alleged that this being none the less exists by a metaphysical necessity, we are still waiting for an explanation of this kind of necessity. The existence of this being is not logically necessary; it does not exist in all logically possible worlds; in what way, then, does it necessarily exist in this world and satisfy the demand for a sufficient reasonl2

My contention is that on a proper understanding of whar a self- explanatory being is, this kind of attack on Leibniz’ cosmological argument can be shown unsuccessful.

M AC K 1 E ‘S C H ALLEN G E

As Mackie describes it, Leibniz’ argument begins with the obser- vation that each thing in the world is contingent, and thus the world as a whole is itself contingent. Making use of the principle of sufficient reason, “that nothing exists without a sufficient reason why it is thus

Laura L. Garcia received her B.A. from Westmoni College in 1977 and her Ph. D. in philosophy from rhe University of Norre Dame in 1983. She is currently a Visiting Assistant Professor at the Catholic University of America. Her interests and most recent publications are in philosophical theology.

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rather than otherwise,”’ Leibniz concludes that only a necessary being can explain the existence of the whole set of contingent entities and events. Mackie summarizes Leibniz’ argument as follows: “There must be a sufficient reasonfor the world which is other than the world. ‘This will have to be a necessary being, which contains its own sufficient reason for existence.”4 As I read Mackie, he wishes to challenge the supposed connection between essence and existence that obtains for a necessary being. If the being a t the conclusion of the cosmological argument is a being that is self-explanatory, i t seems that this requires a link between the very concept of the being and existence such that the question ‘Why does i t exist?’ makes no sense. Unless there is some conceptual tie between the essence or concept and the existence of the being, the fact that the being exists a t all still requires explanation. Its non-existence is “logically possible” as Mackie puts it, and he apparently means by this that the being’s nonexistence is conceivable. Someone who grasps the concept of the being can still be in doubt about whether the beingexists, about whether the concept is instantiated. And Mackie’s claim is that this is true for every concept, “no matter :how much it contains.”

Many defenders of theism will contend that necessary existence is contained in the very concept of God-a being who failed to exist necessarily would not be God on this view. Even so, Mackie argues, whether or not there is a God remains undecided o r open to question. If this theistic concept of God is instantiated a t all, then it is instantiated in every possible world, but there will still be a question as to whether the concept is instantiated. (Actually, the question will be whether the concept is instantiated in any possible world, since if it is, then there exists in that world a being that exists in every possible world, including the actual world.) Genuine existence cannot be analytically contained within a concept; things cannot be defined into existence. These are the Kantian intuitions that lie behind Mackie’s objection to Leibniz. Unless there is some sort of logical or conceptual tie between the essence of a being and actual existence, says Mackie, the fact that the being does exist (even if true) cannot be a self-explanatory fact. Its nonexistence remains a logical possibility, i.e., a conceivable state of affairs, so the question a s to why it in fact exists will remain. This line of argumentation has a kind of leveling effect in that it places all beings on a par with respect to requiring a n explanation. If it is true that contingent beings require explanation because they are conceivably non-existent, the very same thing holds for every being-its non- existence is conceivable, and thus its existence requires an explanation. One cannot tell by scrutinizing a concept whether or not the concept has application-whether or not i t is exemplified by anything. Thus, according to Mackie, the sort of self-explanatory being Leibniz’ proof requires is not available to him.

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ESSENCE A N D EXISTENCE

To respond to Mackie’s challenge, a defender of the cosmological argument must show that it is in fact possible for a being to contain its own sufficient reason, to be self-explanatory. But exactly what sort of tie between essence and existence is required here? One analysis of what it is for an essence or concept to include a property or feature would be the following:

A concept C includes a property P if and only if necessarily, any object that exemplifies C exemplifies P (or exhibits P).

Understood in this way, it follows that every concept includes existence, since it is impossible for an object to exemplify a concept if the object does not exist.5 But clearly this is not the link between essence and existence that is supposed to hold for a self-explanatory being. Perhaps it would be better to phrase Mackie’s question this way: can there beany essence (property) that is necessarily instantiated? This question can be understood in two different ways, depending on how we understand the type of necessity involved.

One way of interpreting this last question is to see it as a request for a concept that obviously or self-evidently must be instantiated. This interpretation calls for a connection between the concept of a being (the subject) and necessary instantiation (the predicate) that is available to our immediate apprehension. The connection would be a conceptual or ‘logical’ one (in Mackie’s sense), and the conceptual connection would in turn be the reason for the ontologicalclaim that there must b e a being that instantiates the essence. On this reading, there need not be a single being that itself exists in every possible world, but in every possible world there is some being that instantiates the essence; of course if we are considering an individual essence, then the same being will instantiate it in every possible world. Are there any properties or essences that have this kind of conceptual tie to necessary instantiation? Perhaps not, but the relevance of this point is unclear. Many philosophers would argue that propositions, properties and numbers exist necessarily and that this can be shown a priori, even though the concept of, say, the number seven is not self-evidently one that must be instantiated. Similarly, Alvin Plantinga’s version of the ontological argument attempts to show that the property of maximal greatness must be exemplified, but Plantinga does not see this as a conceptual truth. On the other hand, Plantinga’s argument is apriori in that there is no appeal to contingent, empirical truths, so perhaps in a weaker sense one could say that this essence (the property of maximal greatness) conceptually includes existence (is necessarily instantiated, reading ‘necessarily’ in Mackie’s conceptual tie sense). But even this weaker claim is not the claim made by the cosmological argument, 1 think.

A second way of reading the question ‘Is there any essence that is necessarily instantiated?’omits any reference to our knowledge or grasp

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oftheconnection between thesubject and predicate: it might be phrased more clearly as ‘Is there any essence that is instantiatedin every possible world?’(A possible world should be understood to mean a world that is metaphysically possible, in the sense defined by Alvin Plantinga.)h Surely everyone who accepts the necessary existence of abstract objects would answer the second question in the affirmative, as would those who endorse the ontological argument. Such persons hold that there (are sound arguments showing that propositions or numbers or God exist in every possible world. On their view, necessary beings in this sense are clearly possible.

Perhaps Mackie wishes to deny that there are necessary beings in this second sense, but whether he does or does not is not really to the point. It seems to me that his concern is not over whether there could be beings that exist in every possible world, but wheter there could be a se1F explanatory being. That is, his focus seems to be on the first reading of the question. I take it that as Mackie sees it, ( I ) a being is self- explanatory (is its own sufficient reason) only if there is a strong conceptual tie between the concept or essence of the being and necessary instantiation. And Mackie believes that (2) such a conceptual tie is never available for any concept you pick, “no matter how much it contains.”Now the ontologicalargument is an attempt to show that one can at least provide some kind of apr ior i tie in the case of the concept of God, but this only redirects our attention to a different argument. Is there any independent response for Leibniz to make to Mackie’s challenge? 1 believe there is.

LEIBNIZ’ LOOPHOLE

Let us leave aside for the purposes of this inquiry the question of whether or not Mackie is right in his claim (2) that no concept is conceptually tied to necessary instantiation. That is, let us accept the claim that for any concept or essence, its noninstantiation is conceivable- there is no apparent self-contradiction involved in denying that the concept is exemplified. I take this t o be in line with the spirit of Kant that Mackie invokes from time to time. Does it follow from this claim that no being is self-explanatory? 1 think not, since it could be that some being’s essence is necessarily instantiated in our second sense (in- stantiated in every possible world) whether we recognize it or not. And such a being would be self-explanatory in one sense-it would be a being for whom the question ‘Why does it exist?’does not arise because it must exist and cannot have failed to exist. In short, 1 think Leibniz would deny Mackie’s claim in (1) that a being is self-explanatory only if its nonexistence is inconceivable. Rather, Leibniz might well support ( I ’): a being is self-explanatory if its nonexistence is ontologically impossible, if it exists in every possible world.

Is there any way of choosing between (1) and (l’)? Imagine a case for (1) along these lines: if we read Leibniz as requiring for every fact a

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sufficient reason why it is true, then it would seem that there must be a sufficient reason even for necessary truths. The primary way of providing a reason why a necessary truth is true would be to show that there is a conceptual tie between the subject and the predicate. Thus, where there is no conceptual tie between the concept of a being and necessary instantiation, we have no reason to believe that the claim that the being exists is a necessary truth.

Suppose that Leibniz did or would adopt the stringent reading of the principle of sufficient reason in which every truth requires a sufficient reason why it is true. Even so, Leibnizcould claim that one has reached a self-explanatory being when one reaches a being whose essence is conceptually tied to necessary instantiation regardless of whether we see or recognize the c ~ n n e c t i o n . ~ Leibniz himself suggests that the sufficient reason behind many truths cannot be known to us,* and perhaps for the existence of self-explanatory beings this is often the case. God “has the reason for his being in himself,”as Leibniz puts it? but it might well be that this reason is unknown to us. This is not to say that the reason could not be known by a higher being.

But we need not interpret Leibni~’ principle of sufficient reason along these stringent lines. It may be that only contingent beings require an explanation as t o their existence. Or again, it may be that for some necessary truths, e.g. complicated mathematical theorems, their sufficient reason may lie in the fact that they follow from other necessary truths. It is not necessary for every one of these truths that its falsehood should be inconceivable-rather, we know its falsehood is impossible on the basis of the proof. Similarly, that God’s existence is self-explanatory in the context of the cosmological argument may be not because it is self-evident that God exists but because a necessary being is the only being that could provide a satisfactory ground for the existence of contingent beings. The beings of our experience are conceivably nonexistent and hence contingent (possibly nonexistent), Leibniz argues. Since they might not have existed, we require an explanation as to why they d o exist. An explanation appealing to other contingent beings merely raises the question again with regard to those beings. Thus, a satisfactory explanation is provided only b y a necessary being that could not have failed to exist. Perhaps this being is itself conceivably nonexistent, but it is known to be metaphysically necessary on the basis of the argument, just as certain mathematical theorems that are conceivably false are shown to be necessary on the basis of a mathematical proof. One may say either that Leibniz’necessary being is self-explanatory in that it needs no explanation of its existence or that it is self-explanatory in that its essence includes existence in a way that is evident to anyone who,fully grasps its essence.

CONCEIVABILITY AND POSS 1BI LlTY

Would matter be a possible candidate for filling this description? Apparently not, since matter’s nonexistence is conceivable. But more

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needs to be said about what follows from such a claim. Mackie characterizes the implications as follows: “We ordinarily assume that for any logically possible statement or conjunction of statements there is at least one possible world that realizes i t . That is, we d o ordinarily expect to be able to argue from non-contradiction to possibility and thence to a possible world.”lO I assume Mackie means to endorse the move from conceivability to possibility, not from lack of contradiction in a narrower sense to possibility. Many propositions which are not contradictory in that no contradiction can bederived from them in first order logic are nonetheless impossible. Examples are that the ball is red all over and green all over at the same time and that triangularity is brighter than circularity.11 But 1 wish to suggest that even conceivability is only a necessary condition for metaphysical possibility (truth in some possible world), not a sufficient condition. It is true that a proposition that is inconceivable is also impossible and that the strength of this inference is essential to our ability to reason and to make sense of our beliefs. However, that a proposition is conceivable confers only what I will call prima ,facie possibility on it. This is due to the fact that occasionally what seems to be a perfectly conceivable proposition turns out on closer scrutiny to be impossible. For example, it might seem not only conceivable but even necessary to some that for every property there can be a set of objects that exemplify that property or that there is a set of all sets not members of themselves, but these propositions are in fact necessarily false. Similarly, Goldbach’s Conjecture is either necessarily true or necessarily false and it is not yet known which it is. Still, both the theorem and its denial seem eminently conceivable, and an unchecked move from conceivability to possibility would mean that the theorem should be viewed as both necessary and impossible.

These unhappy results indicate that conceivability alone is not enough to guarantee possibility-truth in some possible world. I f instead one thinks of the conceivability of a proposition p as conferring prima,facie possibility on p, then when p is conceivable one may accept that p is possible for present purposes unless one finds that the possibility of p is incompatible with other propositions one believes to be true. (Of course this incompatibility need not be resolved by giving up the claim that p is possible. I t could also be resolved by withholding belief on whether or not p is possible or by surrendering the propositions that contradict that claim, though often these propositions are better known or better supported than the claim that p is possible.) What is conceivable is thus a guide to what is possible, though not an infallible guide. And what is conceivable but proves to be impossible does not cease to be conceivable-not every impossible proposition is inconceivable.

This brings us back to Mackie’s question: “Why, for example, might there not be a permanent stock of matter whose essence did not involve existence but which did not derive its existence from anything else?”12

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The cosmological argument concludes to the existence of an underived being, but why may not matter serve in this capacity? Although it is true that for any material being its nonexistence is conceivable, the same holds for any being. The general principle we accepted earlier was that necessarily, for any property (or concept) P and any being x, if x has P then x is conceivably contingent. Since the consequent of this conditional (that x is conceivably contingent) is necessarily true, the conditional itself is necessarily true regardless of what we substitute for P. Every property is such that it is conceivably uninstantiated. The problem is t o decide which properties are such that they can be instantiated by necessary beings (those that exist in every possible world) and which properties can be exemplified only by contingent beings (those that d o not exist in every possible world). Candidates for the latter category are properties like beinga mouse, being two feel long and being made of glass, since these properties are exemplified only by corporeal objects that are clearly destructible and that are destroyed regularly in our experience. If certain abstract objects are necessary beings, then there are also members of the former category (properties exemplifiable by necessary being$)-examples here would be being true, being divisible by three and being incorporeal. It may be possible on this basis alone to decide the question as to whether or not the necessary being at the conclusion of the cosmological argument could be material. Since that being is either material o r immaterial and the material objects of our experience are contingent and the necessary objects we know of are immaterial, one may reasonably prefer to place the necessary cause of the argument in the category of immaterial entities simply on those grounds. Here the argument is that im- materiality seems to fit better with necessary existence than does materiality.

There is a different argument against Mackie’s suggestion that a stock of matter/ energy might exist necessarily, though the premises of this argument are more controversial. Nevertheless, I believe it captures the real reason why someone like Leibniz would reject Mackie’s proposal. This argument requires a distinction between two kinds of con- ceivability. Let us say that a proposition is weakly conceivable if one sees no conceptual incoherence in it, if its denial does not seem impossible or contradictory. To say a proposition is weakly conceivable is t o deny that it is inconceivable. On the other hand, a proposition may be strongly conceivable, in that it seems to us that the proposition can be true, that the state of affairs it describes is clearly realizable. If a proposition is strongly conceivable it is also weakly conceivable, though the reverse is not always true. This distinction may be difficult to apply in every case, but I think it is a legitimate one. After all, when we say that our dog’s nonexistence is conceivable we mean to say more than just that her nonexistence is not impossible. We can just see that she could fail to exist, that she might not have existed at all, where this is a stronger claim than the first.

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My suggestion is that normally when people say that God's nonexistence is conceivable or that numbers might not have existed they mean to assert that this is kieakly conceivable, that there is no obvious absurdity in it. Whereas when they say that matter/energy might not have existed they mean to assert that this is szrong1.y conceivable. Matter/ energy could have had very different intrinsic properties (according to the physicists); there could have been less or more of it; it might not have existed at all. Suppose, then, that the nonexistence of matter is strongly conceivable in our sense-what follows from this? I claimed above that weak conceivability confers only prima facie possibility upon a proposition and that this can be defeated by further information one acquires, and that the move from inconceivability to impossibility cannot be defeated in this way. What of strong conceivability? Here my intuitions are more tentative but I a m inclined to the view that the move from strong conceivability to possibility cannot be overruled. Thus if the nonexistence of matter/ energy itself is strongly conceivable, matter cannot be the necessary being at the conclusion of the argument. Even if the move from strong conceivability to possibility can be overruled, there is no reason to think that it is in this case. There is no reason to think that matter, though conceivably contingent, is actually necessary. Further, even if it could be successfully argued that matter / energy exists necessarily, one must still show that i t could function as the cause of all of the contingent beings in the universe, including immaterial souls if there are such. And it seems to me that this project will be problematic in the extreme.

The properties one ascribes to the necessary being of the cosmological argument should be properties that comport well with the two features we already know apply to it-necessity and being the causal source o f contingent beings. Thus, the properties should be ones whose noninstantiation is not strongly conceivable. Most of the properties traditionally ascribed to God fit this requirement-immateriality, omniscience, omnipotence, perfect goodness, and so on. So the principle we accepted above should be read as insisting only that the noninstantiation of every property is weakly conceivable, not that it is strongly conceivable. Given that the traditional concept of God and the concept of the necessary being at the conclusion of the cosmological argument share many of the same properties, it is surely more appropriate t o identify the necessary being with God than to identify it with matter. At least it seems reasonable to deny that the being is a permanent stock of matter.

CONCLUSION

I have disagreed here with Mackie's claim that the cosmological argument as advanced by Leibniz must rely on the success of the ontological argument in finding a conceptual (or even an a priori) lie

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between God’s essence and his existence. Rather, I believe the self- explanatory ground of being sought by Leibniz is a being that is ontologically necessary and so does not require an extrinsic explanation of its existence. Mackie says that “we have no understanding of how it could be true of this being that it is not the case that it might not have existed,”l3 but we d o not need such an understanding. The argument is to the actual existence of this being, and from there to its possible existence.

Mackie could argue as a last resort that the self-explanatory being cannot be actual because it is not possible-it is in fact impossible. But surely it is possible (conceivable) that there is a being that exists in every possible world, and is such that “it is not the case that it might not have existed,”even if no being is such that its essence is conceptually linked to necessary instantiation. Since it is conceivable that a self-explanatory being exists (where this is a being that exists in every possible world), there isprima faciereason to think that sucha being is possible. Mackie might add that if he is correct in claiming that for any being, its nonexistence is also conceivable, there is prima facie reason to think that the being’s nonexistence is also possible. But the being in question is one whose existence is either necessary or impossible (or better, its essence is either necessarily instantiated or necessarily uninstantiated). How can one decide which it is? A Leibnizian might suggest that one decides on independent grounds, by the fact that the being is required to explain the existence of contingent beings. The cosmological argument (if successful) shows that there is such a being, and hence that the being is possible (as well as necessary).

These remarks have been directed to just one of the questions Mackie asks of Leibniz-“ ‘How can there be a necessary being, one that contains its own sufficient reason?’ ” His second challenge-“ ‘How do we know that everything must have a sufficient reason?’”l4- is equally important and any defense of the cosmological argument must include a response to it. My aim in this paper has been to answer Mackie’s first question and to argue that Leibniz’project is not an impossible one; that it is successful remains to be shown.15

NOTES

I Oxford: Clarendon Press, 1982. 2 Ibid., p. 84. 3 G. W. Leibniz, “Correspondence with Clarke” in Laibniz: Philosophical Wrifings, tr.

by Mary Morris (London: Dent and Sons, 1961), p. 200. Miracle of Theism, p. 82.

5 1 assume here that there are no nonexistent (merely possible) objects. 6 Cf. The Nafure ofNecessify (Oxford: Clarendon Press, 1974), ch. 4. Plantinga calls

this “broadly logical necessity.” 7 Indeed, when St. Thomas makes the claim that God is the only being whoseessence is

existence (and so is necessarily instantiated), he also insists that God’s essence is not knowable by us. So he cannot be reading this claim as involving a conceptual tie between God’s essence and his existence such that we could recognize it.

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“Monadology.” para. 32, op. cit.. pp. 8-9. Ibid., p. I I .

This point is developed in Alvin Platinga. “15 Theism Really a Miracle’?” Fairh and 1 ’ ) Mackic. Miracle oj Theism, p. 60.

Philosophy, 3 ( 1 Y86), p. 1 17. I ? Miracle qf Theism, p. Y I .

Ibid., p. 84. I‘ Ibid., p. 82. I’ I wish to thank Jorge Garcia and Alvin Plantinga Tor some very helpful discussions of

the ideas in this paper.

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