The deductive cosmological argument from contingency has a long and illustrious history. It’s been exposited and defended by the likes of, e.g., G.W. Leibniz, Samuel Clarke, and recently (e.g.) Stephen T. Davis, Ronald Nash, Robert Koons, and Alexander Pruss. However, a number of contemporary theists seem to shy away from defending it, such as J.P. Moreland, Peter Van Inwagen, and William Lane Craig (although Craig seems to have warmed up to it slightly in recent years, given his more-positive-than-usual assessment of it in his essay in The Rationality of Theism). In this post, I will exposit the Leibnizian cosmological argument from contingency. Then, I will discuss some common objections to the argument that don't seem to work. Finally, I will discuss several decisive criticisms of the argument. In the appendix, I exposit and critique a recent defense of PSR.
This version of the cosmological argument has been given a number of construals, depending on how its proponents spell out the notions of a contingent being and the Principle of Sufficient Reason (PSR). One common way to spell out these notions is as follows:
A contingent being or state of affairs is a being or state of affairs that exists, but doesn’t have to – its nonexistence is logically (or metaphysically) possible. So, for example, rocks, trees, and you and I are contingent beings, and George W. Bush being the current U.S. President is a contingent state of affairs. By contrast, a necessary being or state of affairs is a being or state of affairs that exists or obtains of logical (or metaphysical) necessity – to use possible worlds talk, one that exists or obtains in all possible worlds. So, for example, if Anselm’s God exists, then it is a necessary being.
Finally, PSR states that (a) for every being that exists, there is a sufficient reason for why it exists, and (b) for every state of affairs, there is a sufficient reason for why it obtains. PSR has prima facie plausibility, and is often defended by offering one or more of the following three considerations. First, it seems to make sense of our intuitions when we reflect on sample cases. So, for example, suppose there is a ball on the lawn in your front yard. No one would say that there is no sufficient reason for why the ball exists, or why it’s there on the lawn. Obviously, the ball has an explanation for its origin (in a toy factory), its continued existence (in terms of, e.g., the properties of the particles that constitute the ball), and its being on the lawn now (your daughter left it there). The same sorts of explanations seem to generalize to any case we can think of. Therefore, we have some support for PSR based on reflection on cases. Second, some have argued that PSR is self-evident. Self-evident propositions are those that can be seen to be true merely by coming to understand what they assert. That is, once you understand what they mean, you can see that they’re true. So, for example, consider the proposition, “all triangles have three angles”. Once I understand the constituent concepts of this proposition, I can see that it’s true. Similarly for “nothing can be red all over and green all over at the same time.” And similarly, say some proponents of the contingency argument, for PSR. Third, even if one remains unpersuaded by the previous two considerations, one may think that it’s a presupposition of rational thought. Compare: Although it's notoriously difficult to justiify the existence of material objects, and the existence of a past, it nonetheless seems pathological to deny that material objects exist, or to deny that the universe has existed for more than ten minutes (as opposed to thinking that it was created ten minutes ago, with an appearance of age, and with false memories of a longer past). All sane people accept these propositions, and -- say some proponents of the argument from contingency -- the same is true of PSR. Thus, even if you think we can’t prove it, you must accept it to be a rational agent. Given these notions, we may now state the argument.
It’s undeniable that contingent beings exist. After all, we came into existence, and could go out of existence without much trouble. The same is true of rocks, trees, our planet, and in fact every object in the universe. In fact, the universe itself seems to be just one big contingent being. If so, then by PSR, it has a sufficient reason for its existence. Now since it’s a contingent being, it can’t account for it’s own existence in terms of its own nature, even if it has existed forever. For even if the contingent universe existed forever, the following contingent state of affairs would obtain:
(CF1) There being an eternally existent contingent universe.
But if so, then by PSR, there is a sufficient reason for why CF1 obtains, in which case we must look for a reason beyond our contingent universe.
Now whatever that “something” is, it can’t just be more contingent beings. For even our universe is explained in terms of an infinite series of contingent beings, the following contingent state of affairs would obtain:
(CF2) There being an infinite series of contingent beings.
But if so, then by PSR, there is a sufficient reason for why the infinite series of contingent beings exists or why CF2 obtains. In short, no matter how many contingent beings we throw into the explanatory “pot”, the existence of our contingent universe – or any contingent being whatever, for that matter – cannot be sufficiently accounted for purely in terms of contingent beings. But if not, then the sufficient reason for the existence of our contingent universe must be in terms of at least one necessary being. And, as Aquinas would say, “this we all call ‘God’.
II: Giving the Argument its Due: A Defense Against Common Objections
In this section, I continue the task of giving the contingency argument its due. To that end, I briefly discuss three criticisms of the deductive argument from contingency that don’t seem to work. Here I’m just summarizing William Rowe’s points from his Philosophy of Religion (Belmont, Ca: Wadsworth, 1978), pp. 16-30.
1. Dependence and the fallacy of composition:
1.1 The argument fallaciously assumes that because each member of the collection of beings within the universe is dependent, that therefore the whole collection of such beings is itself dependent. But this doesn’t follow.
1.2 Reply: It would be fallacious to assume this, but the defender of the cosmological argument need not assume it for the argument to work. Rather, since the existence of the collection of dependent beings is a positive fact, then it follows from PSR alone – i.e., without the need to rely on an inference from dependence of the parts to dependence of the whole -- that there must be a sufficient reason for why the collection exists.
2. Causation and the fallacy of composition:
2.1 The argument fallaciously assumes that because each member of the collection of dependent beings has a cause, that therefore the whole collection of dependent beings has a cause. But this doesn’t follow.
2.2 Reply: It would be fallacious to assume this, but the defender of the cosmological argument need not assume it for the argument to work. Rather, since the existence of the collection of dependent beings is a positive fact, then it follows from PSR alone – i.e., without the need to rely on an inference from the need for a cause of the parts to a need from a cause of the whole -- that there must be a sufficient reason for why the collection exists.
3. Nothing’s left to explain
3.1 The defender of the cosmological argument fails to see that once the existence of each member of a collection of dependent beings is explained, the existence of the whole collection is thereby explained.
3.2 Reply: It’s not true that explaining why each member of *any* collection of dependent beings exists entails an explanation for why the whole collection exists – why there are dependent beings at all. True, there are cases *of certain sorts* in which explaining the former entails explaining the latter. For example, if a necessary being were the direct cause of each dependent being in the universe, then it would be true that explaining why each dependent being exists would thereby entail an explanation for why the whole collection exists, and why there are dependent beings at all. However, there are cases in which it wouldn’t; just take the necessary being out the previous case, and imagine each dependent being as caused by one of the others. In such a case, explaining why each dependent being exists wouldn’t explain why there are dependent beings at all.
III: Why the Argument Ultimately Fails
This section completes my discussion of the deductive cosmological argument from contingency. In the previous section, I considered a set of objections to the argument that didn't seem to be persuasive. The moral of that discussion seemed to be that the argument stands or falls with the viability of PSR.
Here, I offer objections to PSR that seem to have some force. These criticisms aren’t original with me, but rather are standard objections (except perhaps the last one, although it's based on ideas of other authors). Furthermore, I don’t mean to imply that there aren’t other versions of the argument from contingency that may avoid these criticisms. However, they do seem to apply to the variants of the argument that one finds in standard “intermediate-level” apologetics books. The criticisms can be divided into two broad categories: (i) those that undercut the reasons offered for accepting PSR, and (ii) those that indicate that PSR is positively false or unreasonable.
1. Type-(i) Criticisms:
1.1 Contrary to what its proponents often assert, PSR does not seem to be supported by reflection on cases. Rather what such reflections support is the weaker principle that objects and events are explained in terms of antecedent causes and conditions. In actual practice, ordinary individuals and scientists explain the existence of objects and events in terms of antecedent causes and conditions, provisionally taking the latter things to be brute facts unless or until they, too, can be further explained. But the prinicple implicit in this sort of search for explanations isn't sufficient to generate the need for an explanation of the universe as a whole in terms of a necessary being.[i]
1.2 Contrary to what some of its proponents assert, PSR does not seem to be self-evident. For what makes a proposition self-evident is that grasping its meaning is sufficient for seeing that it’s true. Consider the two standard categories of self-evident propositions: analytic a priori propositions and synthetic a priori propositions. Both sorts of propositions are knowable independently of empirical investigation of the world. But they differ in that the former (analytic a priori propositions) are tautologous and uninformative, while the latter are not. So, for example, "All bachelors are unmarried" is an analytic a priori proposition, while "Nothing can be red all over and green all over at the same time" is arguably a synthetic a priori proposition.
Now consider PSR: (a) For every object, there is a sufficient reason for why it exists; (b) for every positive state of affairs, there is a sufficient reason for why it obtains. This isn't a tautology; so it's not analytic a priori. Furthermore, although it's a substantive claim, its truth or falsity is not evident merely by reflecting on its constituent conceps. Thus, it doesn't seem to be synthetic a priori, either. Perhaps there is another category of self-evident propositions, but if so, PSR seems not to belong to it. For what makes a proposition self-evident is that one can see that it's true merely be reflecting on its contituent concepts, and we have seen that PSR doesn't safisfy this condition.
1.3 Even if PSR were a presupposition of reason, it wouldn’t follow that it would then be true. But in any case, PSR does not seem to be a presupposition of reason. Rather, again, reason only seems to demand that the existence of each object or fact is explained in terms of antecedent causes and conditions, which are provisionally taken as brute facts unless or until they, in turn, can be explained. Reason does not seem to require anything beyond this.[ii]
2. Type-(ii) Criticisms:
2.1 PSR absurdly entails that everything obtains of necessity. The argument for this can be stated as follows. Consider the conjunction of all contingent facts (CCF). By PSR, there is a sufficient reason for CCF. Now the sufficient reason for CCF is itself either contingent or necessary. But it can’t be contingent, because then it would represent a contingent fact, in which case it would itself be a part of the CCF. But contingent facts don’t contain within themselves the sufficient reason for why they obtain – let alone the sufficient reason for why the CCF obtains. Thus, the sufficient reason for CCF must be necessary. But whatever is entailed by a necessary truth is itself necessary, in which case all truths would be necessary truths, and the referents they represent would obtain of necessity. But this is absurd. Therefore, PSR is false. [iii]
2.2 The following scenario is prima facie possible: there are just two kinds of beings that exist: contingent-and-dependent beings (e.g., rocks, trees, planets, galaxies, you and me) and contingent-yet-independent, “free-standing” beings, out of which all contingent-and-dependent beings are made (perhaps matter-energy is like this). If so, then even though there are possible worlds at which the contingent-yet-independent beings don’t exist, they are eternal and indestructible at all possible worlds in which they *do* exist (interestingly, some theists -- e.g., Richard Swinburne -- take God to be just such a being). On this account, then, there are contingent beings that come to be and pass away – viz., the contingent-and-dependent beings. But the beings out of which they’re made – i.e., the contingent-yet-independent beings -- do not; nor can they [iv]. This scenario seems possible. But if so, then since PSR entails that such a state of affairs is impossible, then so much the worse for PSR.
The basic point here is that PSR assumes that dependent beings must have their ultimate explanation in terms of *necessarily existent* independent beings (beings who exist in all possible worlds), when in fact *essentially* independent beings (beings that are independent at all possible worlds *in which they exist*) are all that are needed to do the requisite explanatory work. PSR entails that this isn't enough: if there are any essentially independent, indestructible, free-standing beings, then these must be *further* explained in terms of a *necessarily existent* being. But surely this is explanatory overkill, and since PSR entails that such further explanations are required, this implication undercuts any prima facie plausibility PSR may seem to have had.
These criticisms have varying degrees of force. However, it seems to me that criticism 2.2 is an undercutting defeater for PSR, and that criticism 2.1 is a rebutting defeater of PSR. But if these things are so, then the argument from contingency is defeated.
APPENDIX: A Recent Defense of PSR
(Note: some things I say here are of a technical nature, and thus will probably only be of interest to those with some background in philosophy)
A number of philosophers have attempted to revive the Leibnizian cosmological argument in recent years by advancing a weaker version of PSR. According to their version of PSR, every contingent being has a *possible* explanation in terms of something else. That is, every contingent being is such that there is at least one possible world at which it has an explanation for why it exists. Call this version of PSR, 'Modal PSR'.
Now some authors -- in particular, Garrett DeWeese and Joshua Rasmussen[v] -- offer an argument for Modal PSR . Now I think their argument has a couple of problems, but here I just want to mention one that I think is decisive: The argument uses Modal PSR as a premise to derive the standard version of PSR we discussed above. But this premise is implausible at best, and outright false at worst. For unless they just beg the question and assume that there are no possible beings that lack a sufficient reason, then they must be claiming that, even if there *are* possible worlds at which a given contingent beings lacks a sufficient reason, there are *other* possible worlds at which it does. But this is implausible, For It seems to me that the only way to accept Modal PSR is to reject origin essentialism. Allow me to me unpack and explain this criticism below:
Suppose origin essentialism is true, and suppose we've got our hands on a universe, and we give it a Kripkean baptism: (pointing to the universe) "Let *that* be called 'Uni'. 'Uni' is now a Kripkean rigid designator -- it refers to *that* universe in all possible worlds in which it exists.
So now we have a way to hold Uni fixed, so we can start considering modal claims about *it*. Well, there are two relevant possibilities for us to consider here: (i) Uni has its origin in the causal power of a divine being,and (ii) Uni has no origin. If (i), then, by origin essentialism, this is an essential property of Uni, in which case there is no possible world in which Uni lacks such an origin.
If (ii), then Uni lacks an origin in the causal activity of a divine being, and so *this* fact about Uni is essential to it, in which case there is no possible world in which it has an origin in the causal activity of a divine being.
The moral, then, is that if we accept origin essentialism like good Kripkeans, then whether a universe has an explanation in terms of a divine being doesn't vary from world to world. But if so, then Modal PSR is of no help unless we know *beforehand* whether our universe has its origin in the causal activity of a divine being. But if we already knew *that*, then the contingency argument would be superfluous.
Of course, one could always reject origin essentialism, or restrict its scope in a way favorable to the argument, but then the audience for the argument shrinks considerably.
i. This is a rough paraphrase of one of J.L. Mackie’s objections in The Miracle of Theism (Oxford: Oxford UP, 1983), pp. 84-87.
ii. See ibid.
iii. This objection is a rough paraphrase of one of Peter Van Inwagen’s objections in his textbook, Metaphysics, 2nd edition (Boulder: Westview Press, 2002), pp. 119-122.
iv .Another way to see how this could be: contingent-yet-independent beings have indestructibility as an essential property: they are indestructible and everlasting at all possible worlds in which they exist. However, there are possible worlds at which they don’t exist.
v. See their chapter of the recent apologetics book, In Defense of Natural Theology (InterVarsity Press, 2005).