Monday, September 19, 2011

Leibniz's Cosmological Argument

A common formulation of Leibniz’s Cosmological Argument is as follows:
1.    Everything that exists has an explanation of its existence (either in the necessity of its own nature or in an external cause).
2.    If the universe has an explanation of its existence, that explanation is God.
3.    The universe exists.
4.    Therefore, the universe has an explanation of its existence [1, 3].
5.    Therefore, the explanation of the universe’s existence is God [2, 4].[1]
Since this is a logically valid argument (that is, it follows a proper form known as modus ponens), if one wishes to avoid the conclusion then she must deny at least one or more of the premises. (3) is true so long as one is being rational. Moreover, consider that the first premise, also known as the Principle of Sufficient Reason, is highly intuitive. Some may retort the PSR is highly controversial, but I suspect the main reason it’s so is that people wish to avoid the conclusion of a God, not because things or state of affairs being explained is so controversial.
As Craig notes, this PSR is wholly compatible with there being brute facts about the world.[2] This undercuts the major objection to the PSR. He goes on to note that “explicability is the default position and that exceptions to the principle therefore require justification.”[3] That justification doesn’t seem to be forthcoming. Moreover, as Groothuis objects, it seems quite ad hoc to require explanations for existence and states of affairs in science and other areas of life but not as it relates to cosmology or the universe.[4] In fact, it remains literally inexplicable why just anything exists if the PSR is false, ultimately.
Perhaps the skeptic or atheist may wish to accept the PSR (as seems eminently plausible) yet reject (2), or perhaps they reject this in addition to rejecting the PSR. They may wonder just why they should accept that God is the universe’s explanation, if there is one at all. First, one must note the contrapositive of the premise: If the explanation is not God, then the universe has no explanation. This is a line repeated by more than one atheist (including Bertrand Russell, who famously thought there simply was no explanation for why there is something rather than nothing). But since any premise’s truth-value necessitates the same truth-value for its contrapositive, atheists who take Russell’s track are already committed to the truth of (2)!
Perhaps an objector may wish to claim the universe is necessary rather than contingent (and hence affirm [1] and deny [2]). But in that case, not only must the universe exist from an infinite past, but also must exist into the infinite future. That is to say, the universe cannot fail to exist, or cease to exist; there cannot be a state of affairs of nothingness as it relates to the universe. But that is a radical claim. Since we can conceive of the universe’s non-existence, what non-arbitrary reasoning can there be for affirming its necessity?
Next, Groothuis shows reason to reject that the universe just exists without an explanation and that it is necessary. “The metaphysical implication of rejecting the principle of sufficient reason with respect to the cosmos is that the cosmos is meaningless . . . nothing has any ultimate meaning, and . . . everything is gratuitous.” Essentially, this amounts to nihilism.[5] Further, one must reject the universe as a “being that explains itself” because of the highly-plausible conception that the universe can or could have fail/failed to exist. “If the universe were . . . self-explanatory and self-existent, such a question [why is there something rather than nothing?] would be radically out of place—on the order of asking, Why is the law of noncontradiction true?”[6] But it is not so radically out of place.
In conclusion, it seems the PSR is extremely intuitive, the universe exists, and it does not explain itself. But if that is the case, then a final self-explanatory being is in mind; exactly what we call “God.”[7] We may then conclude the God of monotheism is the best (and really, only) candidate for this being. From that, Christian evidences can and should follow. What a great argument!

[1] William Lane Craig, “Argument from Contingency,”, accessed September 19, 2011.

[2] William Lane Craig, Reasonable Faith, 3rd ed. (Wheaton, IL: Crossway, 2008), 107.

[3] Ibid.

[4] Douglas Groothuis, Christian Apologetics (Downers Grove, IL: IVP Academic, 2011), 212-13.

[5] Ibid., 212.

[6] Ibid., 213.

[7] Craig, Reasonable Faith, 99.

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  1. Meh. I don't find this argument compelling in the least. Why does the "explanation for the existence of the Universe" have to be God?

  2. God being posited as thee explanation for the existence of the universe is appealed to because God by definition is an eternal Being (the universe is not eternal), immaterial (the universe is all matter and all of energy), and personal (the universe is a temporal effect of a timeless cause). It's not enough Zilch to just say "I don't like the conclusion of the argument" and then proceed to think that the argument has been refuted. Show where one or more of the premises is false. Otherwise, one has no choice other than to accept the conclusion of the argument.

  3. I've thought that Craig's version of the argument comes on a little strong in premise 2. The reason being that premise 1 really just establishes that if the universe isn't necessary, it has an external cause. Of course, from that we may extrapolate God, but I like to leave it out of the premise and establish an independent argument for the external cause being God.

    My post on the topic here:

    Anyway, I'll be featuring this post on my really recommended posts this week.

  4. Hi zilch thanks for the comment! There is a subtle implication of the PSR's being true and the universe existing contingently, rather than necessarily. It means there is an ultimate explanation. Why? Because an infinite regress of explanation doesn't explain why anything exists in the first place. Consider that even if we argue there are an infinite number of explanations for each existing thing, so that X explains Y, Y explains Z, Z explains A, and so on ad infinitum, we haven't really explained why anything in the set exists at all. We must either posit some kind of necessity, which seems totally ad hoc (and other criticisms addressed above), or else there is some ultimate explanation. But the ultimate explanation cannot be explained by some external cause, for then it is not the ultimate explanation after all. Rather, this UE is explained by the necessity of its own nature. But an ultimate cause explained by the necessity of its own nature is exactly what we mean by God!

  5. Ben, I certainly agree and thanks for the comment! I do think zilch was attempting to deny (2), or at least rather say he does not understand why it should be accepted, at least. But I think then at best his case is that he did not understand the argument for (2), so I attempted to provide one.

  6. Thanks JW for the comments! I agree with you largely, and I had the same thought process. I ultimately chose to stick with Craig's (2) because it is defensible (especially in my comment to zilch above), but I would not oppose making (2) the above conditional you stated. Thus, all opposition would only be able to focus on (1). However, one may claim the affirming of that antecedent might be some kind of argument from ignorance, whereas because we have no argument for the universe's necessity, it is not necessary. But I don't think that charge would stick, since we seem to have good intuitively metaphysical reasons for thinking the universe could be different than it is, or cease to exist, etc. Just some thoughts, and I appreciate yours!

  7. Hey Randy,

    I'm actually a bit puzzled about premise 3, here, and its interaction with premise 1. If we understand the universe to be a thing which exists, then it seems to me that it should be none other than the mereological sum of all of physical reality. But if we're allowing for such a loose principle of composition, then I don't see why we couldn't similarly form a mereological sum of all of existence, call it E. But, then, under the restricted PSR here, E is either a necessary being or requires an external cause for its existence. There can be no external cause for E as everything that exists is a part of E (proper or improper). So, the explanation for the existence of E must be that E is a necessary being. But if E is a necessary being, then should not E's parts be necessary, on pain of violating Leibniz's law? This would then imply that the universe is a necessary being, contrary to supposition.

    What I'm getting at is this: what sort of principle of composition allows for the consideration of the universe as an object subject to the PSR while also disbarring problematic entities like E?

  8. Hi Jake, I certainly appreciate your comment. I don't think entities like E are a problem for non-naturalists with regards to the universe (since they needn't think the universe to be necessary), and I don't think that all existence should be identical with each other (as it is in pantheism). And I agree if an entity like E were to be necessary, its parts would be as well (though God certainly doesn't fit that category). But in any case, I don't think non-materialists are forced into thinking that all existence is itself contained in one some, so that all entities are really just parts of the whole. Now God is the ground of existence in general, so that if God is necessary, existence is necessary, but it wouldn't follow that everything that exists is necessary in this case.

    As to the composition issue, I think the universe is of the sort of composition that tells us if we compose a wall entirely of red legos, we have a red wall. Whereas existence isn't so much a predicate of persons generally, nor is person A's existence identical to person Y's existence. Since the two existences are not of the same "substance" in an analogous way to physical reality on a non-materialist/non-naturalist interpretation, this would mean E doesn't really apply. I hope that helps; I just quickly typed it up once I believed I understood your point. :)

  9. Thanks for the reply, good sir.

    I think you're right in thinking that the non-naturalist (and I think the naturalist) isn't required to admit of the mereological sum of the likes of E. But the potential difficulty is to provide a principle of composition which explains why we should admit the complex mereological sum of physical reality, the universe (U), as an entity for the 3rd premise (and thus a subject for the PSR) and not E.

    You do point at (at least what I take to be) a potential explanation: the material world is all of one sort of substance while, at least given theism, God and all of non-physical reality is of a different substance. So perhaps we can restrict composition to composition with entities of the same substance. This could be plausible enough (even though many mereologists have been perfectly fine with allowing such sums), except I don't think that it avoids the problem.

    For instance, given traditional theism God is not the only mental/spiritual entity. There are angels, demons, etc. Heaven, for instance, is usually taken to be a spiritual realm where other beings, along with the saved human beings, interact or ultimately reside. If we can take the mereological sum of all of physical reality for the purpose of the PSR, then we should similarly be able to take up the mereological sum of all of spiritual/mental reality. Because God is a spiritual/mental being, he would be included in this sum. Now we run into the same problem as before: according to the PSR, this sum is either necessary or has an external cause. Given that we think that the only other possible entities here would be physical ones and that the physical world doesn't cause the spiritual world in any way, we must find that this sum is necessary. But, then, all of the angels, demons, saved human beings, etc, included in this sum would also be necessary beings as opposed to contingently created ones in virtue of being a part of this spiritual universe (as opposed to the physical universe).

    So, it still looks like there is a problem with both accepting the restricted PSR used in the LCA given and the sort of mereological principle necessary for the truth of 3.

  10. Hi Jake. I understand and appreciate your concern and rigor in this area! However, I do not think that all existence of non-material things are in fact similar to themselves in substance. That is, I just think they are similar in, for lack of a better term "type." The "substance" in cases of existence of spiritual beings (or the immaterial) would just be individual souls for humans and spirits for angels and God, who is a spirit himself in Christian theology.

    A soul, distinct from all others, is what makes one ontologically one, and different. Now I am wondering why that cannot be applied to the universe, and I am thinking that it's because just is one undifferentiated whole. That's not to say that there are no differences between material things (as I think it absurd that there is no ontological difference between a table and a cat, for instance), but rather what binds them together is modality and explanation of existence, since the things in the universe come as a result of naturally-occurring events that are not the result of free choices.

    So while all beings who come from the universe are necessary if the universe is necessary, not all beings who come from a necessary being are necessary--if that being has a free will.

  11. Simply asserting that only the Christian God can be the first cause is massive question-begging. I suspect that you do this because there is no good reason to believe such a god exists. If you disagree, plase give a non-question-begging argument.

    The Kalam doesn't work either unless you demonstrate that the "cause" of the universe is personal. Merely asserting it doesn't work. Sorry.

  12. Hi Nightvid. I'm sorry, which premise do you think I assert only on the basis of accepting the conclusion? And what's with the carpet-bomb of comments? :) I do enjoy people commenting though.

    1. Randy, I am a believer but I have a hard time with premise 2. How is it not question begging? I know the typical response Craig gives is that its logically equivalent to the Atheist response but could this be a false dilemma? That would mean the third option is that both the Theism and Atheism are begging the question. What are your thoughts?

    2. Hi Darian, thanks for your question! We must remember that a premise only serves as question-begging if it assumes the truth of an argument's conclusion (or, in this case, one of the conclusions) in itself; in other words, it is question-begging if our only or primary reason for asserting it is the conclusion itself. Now, as it turns out, one does not have to hold either conclusion in order to hold to (2); that's the purpose of Dr. Craig's pointing out that, apart from consideration of this family of arguments (cosmological), atheists are quite content to give the explanation that, in the absence of God (or, since God does not exist), the universe has no explanation. That is (formally) logically equivalent to (2), so that the atheist must abandon this earlier claim in order to avoid the force of (2). So we see it's not question-begging in this sense. But what about *our* reason for affirming this? We can appeal to the implications of (1) and other evidence. For instance, if (1) is true, then the universe, if it exists (which it does), requires an explanation, and it's either an external cause or the necessity of its own nature. Now, most people, when probed, don't believe the universe is necessary (even if it's eternal); but if that is the case, the cause is external. We are justified in using other theistic arguments (such as the kalam), or just the prior probability that it would be God, and not gods (for simplicity's sake). Now, the objector may not like our particular reasons, but, once again, so long as he claims the contrapositive of (2), it's not open to him to deny (2), and unless he tears down all justification for thinking that God is the most probable explanation for the universe, we are justified in asserting (2). So, the objector has to jettison one of his beliefs and attack the justification over a wide-array of arguments. If I were an atheist, I would attempt to deny (1), personally. I also like just stating it as the contrapositive. 2* If God does not exist, then the universe has no explanation. An atheist may better swallow this, as well as theists. It might help to look at it one more way: in order to deny (2), one must say it is the case that the universe has an explanation, and God is not that explanation. In order to deny (2*), one must say it is the case that God does not exist, and the universe has an explanation. Once these logical parameters are set, (2) becomes very difficult to deny. Hope that helped! :)

    3. I also realize in my last example I just gave, it's not strictly the contrapositive. God could exist and not be the explanation of the universe, I suppose. But that's truly odd. :)

  13. Hi Randy, If everything has a reason for its existence, then what would be the reason God exists as a tri-unity as opposed to existing as one or even two persons? [I should note that I am a Christian but this issue just bothered me :)]

    1. Hi James, thanks for your thoughtful question! Now remember, the premise is that "everything has an explanation of its existence, whether in the necessity of its own nature or in an external cause." So God, as a being, finds the explanation of his existence in the necessity of his own nature. Since his own nature is necessary (per definition), and since his nature is to be tri-personal in one being, then the explanation for his being triune is also in necessity. To ask why this is the case is what philosophers call an "unanalyzable fact;" that is, it does make sense to ask what the explanation of God's being triune is, while it doesn't make sense to ask why it is that the explanation is necessary (that would be like asking why is it that a truth is necessary). Now, in one sense, we've already answered that question: God's being triune is necessary because it's part of his nature, which is necessary. In another sense, we cannot answer it, for to ask what makes something the case that it is necessary beyond the necessity itself is to assume that the fact isn't necessary at all! Does that help any?

  14. Coming to this rather later, having found it from a link at Christian CADRE blog.

    It is premise (2) (and its contrapositive!) that I reject.

    "That is to say, the universe cannot fail to exist, or cease to exist; there cannot be a state of affairs of nothingness as it relates to the universe. But that is a radical claim. Since we can conceive of the universe’s non-existence, what non-arbitrary reasoning can there be for affirming its necessity?"

    Why is this any more radical than saying the same of God - besides the obvious fact that you are a Christian, and are already convinced of God as the final cause? We can also conceive of the non-existence of God, by the way, so what is the non-arbitrary reasoning for affirming God's necessity?

    Let us suppose you can address that, then we can also suppose an external cause that is necessary, but is not God. I do not know what that is, but unless you can prove that impossible, your premise (2) is unfounded.

    1. Thanks for your thoughts! Here, though, you offer mostly a tu quoque rather than an actual reason for thinking that the universe could not fail to exist. On the contrary, our best current science suggests the universe *can* fail to exist. So, the same question arises again!

      Second, I can offer non-arbitrary reasons for thinking God is necessary (though it's technically irrelevant to the truth or falsehood of premise 2); namely, arguments from contingency themselves! The whole of contingent things cannot be explained by itself, for it is also contingent or else necessary. If it is necessary, there's no problem with a necessary first cause; if it is contingent, it is a member of itself and does not function as an explanation. There are also considerations from perfect being theology: if God were to exist, then he would be necessarily existent, for example. But all this is, as I mention, irrelevant to the truth of (2)--nothing follows from (2) alone for God's necessary existence, and nothing follows in the reverse--except, perhaps, that the universe might not be necessary.

      As to the last part, what would this external first cause be like? Timeless, spaceless, enormously powerful, personal, beginningless, changeless--all of these are plausibly corollaries of the argument, and all of these look quite a bit like God. It's a bizarre atheism that is willing to admit a being that has all of these qualities but isn't God!


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