Bayes Theorem and the LCA (p. 4)

Home  >  Philosophy  >  Atheism/Theism

Bayes’ Theorem and the LCA

<Prev  |   1   |   2   |   3   |   4   |   Next>

Hypothesis H has some inferential virtues (things that make an inference good) that go beyond merely entailing E, and thus there are inferential virtues go beyond what is reflected Pr(E|H), and are instead reflected (albeit indirectly) in Pr(H).

(1)

It provides an explanation. The big bang theory explains why this cosmic microwave background radiation exists but another hypothesis is that the background radiation exists inexplicably. Both hypotheses entail the existence of cosmic microwave background radiation, but that the big bang theory explains the radiation’s existence is an advantage the other hypothesis doesn’t have. Ceteris paribus, we prefer a hypothesis that explains the existence of a thing over one that merely entails the thing’s existence.

(2)

Precision. Not only does H imply the existence of an explanation, we can actually think of a specific explanation for the contingent universe: an eternal, transcendent, metaphysically necessary personal entity that is the external cause of the universe. Granted, this level of precision is limited, but it’s a big improvement over “there is an explanation and but I can’t think of what it might be at all.” To give an illustration, suppose theory T implies the data but does not explain it. I say we should reject theory T because there might be some unknown hypothesis that explains the data, rather than merely implying it like theory T does. My case for rejecting theory T would be much stronger if I could think of a real example of such an explanation rather than merely asserting that some explanation exists (which would constitute some additional precision for my hypothesis of there being an explanation). Similarly, the fact that we can think of an explanation makes H more likely than it would be otherwise.

My claim here is modest: that items (1) and (2) make H more likely than it would have been without them. Some inferential virtues are also explanatory virtues (things that make an explanation a good one). Some inferential virtues are also explanatory virtues (things that make an explanation a good one). For the specific explanation for H (eternal, transcendent, metaphysically necessary, personal entity as the external cause of the universe), these explanatory virtues include:

(3)	Plausibility. One factor going into plausibility is if it implies fewer falsehoods. I mentioned that an additional factor H has in its favor is that we can actually think of some explanation for the universe. But if the proposed hypothesis is the only known viable explanation and we have no evidence against it (as I claim), the fact that we have such a hypothesis known to us also makes H more likely than it would be otherwise. Think back to the situation of theory T. My case for rejecting theory T would be better if there were no evidence against my explanatory hypothesis.
(4)	Tying in with background knowledge. Fulfilled to an albeit limited extent; we are intimately familiar with personal causes, and we experience personal causes being a reason for why things exist all the time.
(5)	Simplicity. Fulfilled to an albeit limited extent. In my series on the Leibnizian cosmological argument, I posited only those attributes that were needed to explain the existence of the contingent universe: an eternal, transcendent, metaphysically necessary, personal entity that is the external cause of the universe. That these attributes derive so simply from there being an explanation for the existence of the universe makes the explanation more likely than it would be otherwise.
(6)	Explanatory scope. Fulfilled in multiple ways.    (a)  Explaining the cosmos. The existence of a necessary personal being that exists by the necessity of its own nature is sufficient to explain why there is something rather than nothing; the explanation for the necessary being’s existence is the necessity of its own nature, and that necessary being entails the existence of something rather than nothing. In my series on the Leibnizian cosmological argument I noted that the eternal, transcendent, metaphysically necessary, personal entity as the external cause of the universe explains why there is something rather than nothing, why the contingent universe exists, and why the physical universe exists.    (b)  Explaining morality. An eternal, transcendent, necessary personal being (with a few more attributes) also explains objective morality. For more on this, see my argument from ontological simplicity (which is part 1 in my argument from morality series).

These facets of the explanation make the explanation more likely than it would have been without them.[1] My claim is modest: the fact that we can think of an explanation for why there is something rather than nothing that meets criteria (3) through (5) to the extent that they do (e.g. the explanation implies no falsehoods) makes H more likely than it would be otherwise. Just as my case for rejecting theory T would be much improved if I could think of an explanation that met criteria (3) and (4), so my case for rejecting ¬H is improved via (3) and (4). By my lights, the entity explaining not only why there is something rather than nothing but also the existence of objective morality (6b) is a particularly significant item in favor of H, in part because of how simply the existence of an eternal, transcendent, metaphysically necessary entity is extrapolated from the existence of objective morality, but whether I’m right about that heavily depends upon that moral argument for God working.

Shoe On the Other Foot

In addition to assigning a lower prior probability for H to avoid believing it, one disputable point is how much additional evidential weight items (1) through (6) give to “there is an explanation for why there is something rather than nothing;” an atheist could say the evidential improvement is very small. Would such an atheist be right?

Here’s another way to look at it. Suppose the shoe were on the other foot and there being an explanation for why there is something rather than nothing were devastating to theism rather than atheism. Criteria (1) though (6) are met to the same level as the theist’s personal cause hypothesis (the atheist’s explanation is simply and straightforwardly derived from the data; the anti-theistic explanation is the only known viable explanation, etc.). The devastating-to-theism explanation implies no falsehoods and explains why there is something rather than nothing, why the contingent universe exists, and why the physical universe exists. Wouldn’t atheists be reluctant to assign a low prior probability to H in those circumstances? Wouldn’t they be right to do so? I also have a hard time believing atheists wouldn’t use this as fairly significant evidence against theism, particularly in light of the Bayes’ theorem equation that yields a 67% probability of there being an explanation for someone like Al.

Summary and Conclusion

The symbols were these:

• H says there is an explanation for why the universe exists; a sufficient reason for its existence.
• ¬H says is not the case that H is true; there is no reason for why the universe would exist.
• E is the evidence of the universe existing.

The equation was this:

Pr(H|E) =	Pr(H) × Pr(E|H) Pr(H) × Pr(E|H) + Pr(¬H) × Pr(E|¬H)

One advantage H has over “there is no reason for why the universe would exist” is that on H it is more likely that the universe would exist, and for the agnostic (one who considered “there is an explanation for why the universe exists” to be equally as likely as “there is no explanation for why the universe would exist”), that’s enough for the universe’s existence to be fairly significant evidence for H, even if that evidence isn’t overwhelming. Using the above form of Bayes’ theorem to help show that (where Pr(H) = Pr(¬H) = 0.5, Pr(E|H) = 1, and Pr(E|¬H) = 0.5):

Pr(H|E) =	0.5 × 1 0.5 × 1 + 0.5 × 0.5	=	0.5 0.75	= 2⁄3 ≈ 0.67

With the mathematics being airtight, a person who disagrees with the probability result will have to dispute at least one of three things:

1. Pr(E|H) = 1
2. Pr(E|¬H) = 0.5
3. Pr(H) = Pr(¬H) = 0.5

Pr(E|H) is unassailable; there existing an explanation for why the universe exists entails that the universe exists. Pr(E|¬H) is more vulnerable, but considering how special the number zero is to prior probabilities (as credibly illustrated in the case of “zero gods exist”), then abandoning all the background information we would otherwise have about things existing and focusing on just ¬H, it does seem that Pr(E|¬H) = 0.5 or something close to it.

Attacking Pr(H) = Pr(¬H) wouldn’t actually address this key point: a person who is truly agnostic but hadn’t yet considered the evidential force the universe’s existence has for H should re-assign a probability of about 67% for H upon considering such evidence.

In addition to Pr(E|H) = 1, there are various other factors that make H more likely than it would otherwise, and thus there are factors that increase the probability of H that aren’t reflected in Pr(E|H). For example, we can think of a specific explanation for why there is something rather than nothing that (a) implies no falsehoods; (b) is fairly simple (an entity with certain specified attributes that are derived simply and straightforwardly from the data); and (c) has an interesting connection to explaining the existence of objective morality. I’d venture to say that factors (1) though (6) I mentioned push the probability of “there is an explanation for why the universe exists” at least beyond the 70% range.

The degree to which all this counts as evidence for “there is an explanation for the existence of the universe” can be considered by imagining if the tables were turned in atheism’s favor. If in addition to H’s superior explanatory power for the existence of the universe, the devastating-to-theism explanation explained why there is something rather than nothing, why the contingent universe exists, why the physical universe exists, the explanation implied no falsehoods etc. it seems this would constitute fairly significant evidence in favor of atheism. But if that is true, rationality dictates we be consistent and recognize that these factors are equally as favorable to the pro-theism hypothesis of an eternal, transcendent, necessary personal being as the external cause of the universe.

<Prev  |   1   |   2   |   3   |   4   |   Next>

---

[1] I’m oversimplifying this, and some of this can be a bit tricky. Where B is our background knowledge, Pr(H) is really Pr(H|B) (the likelihood of H given some set of background information). For example, for (2), strictly speaking our own existence isn’t part of B. We could include in B something like, “If something were to exist in such a way that we would exist, then there would be personal entities like us who have a reason for why some things exist.” That said, we’re basically considering how one should adjust their probability of H when they hadn’t taken into account E’s evidential force for H.

Bayes’ Theorem and the LCA (p. 3)

Home  >  Philosophy  >  Atheism/Theism

Bayes’ Theorem and the LCA

<Prev  |   1   |   2   |   3   |   4   |   Next>

Pr(E|¬H)

One could make this objection: there are infinitely many ways for there to be something, and only one way for there to be nothing. Pr(E|¬H) should therefore be extremely high, somewhere near 1.

I don’t think this objection is quite as good as it first appears. In some respects simplicity is evidence of truth, and we tend to have a special place in our intellectual hearts for the number zero. To illustrate, consider the case of “How many gods are there?”

Suppose one has no background information regarding the existence of “How many gods are there?” and little to no background information about what sorts of gods, if any exist, are like (e.g. whether they are friendly or hostile, whether they are beautiful or ugly, and whether any have six arms). Given the lack of such background information, what should one’s default view be about whether there are any gods? The default view, it seems to me, is to be truly agnostic, i.e. award “there are no gods” the probability of 50%. Some atheists would award “there are no gods” a default probability greater than 50%, so to broaden the agreement let’s say that the default probability of “there are no gods” is greater than or equal to 50%. But provided we would also award nonzero (even if low) probabilities for “there is exactly one god” and “there are exactly two gods,” we would be giving especially high probability status to there being zero gods, as in “the probability of there being zero gods is greater than or equal to 50%,” thereby awarding the “zero” value to be more probable than any other number of gods and it being no less probable than any other proposition that entails the existence of gods (e.g. “there is a god with six arms”). Notice how significant this is: we are awarding “there are zero gods” a probability value that is no less than all other possibilities combined even when there are infinitely many ways for gods to exist. This strongly suggests, I think, the value of ontological simplicity when coming up with prior probabilities especially as they relate to “there exist things of type X” when there is no background information.

The same principle holds, I believe, for “Why is there something rather than nothing?” Nothing is the ultimate zero, and abandoning all the background information we would otherwise have about things existing and focusing on just ¬H, it seems to me that Pr(E|¬H) is 0.5 or something close to it. The question, “Why is there something rather than nothing?” is interesting precisely because in the absence of a sufficient reason, there being nothing at all to exist seems like a very real possibility.

Prior Probabilities: Pr(H) and Pr(¬H)

Disputing the prior probabilities doesn’t actually affect my main point: a person who is truly agnostic (thinks “there is an explanation for the universe’s existence” is equally likely as “there is no reason for why the universe would exist”) but hadn’t yet considered the evidential force the universe’s existence has for H should re-assign a probability of about 67% for H in the absence of further arguments. That said, one could say that a person who didn’t consider the evidence for E has for H should have Pr(H) be less than Pr(¬H).

One could say that, but in that case the objector would have to argue that in this situation “there is an explanation for the universe’s existence” is less probable than “there is no reason for why the universe would exist.” In abandoning the agnostic’s “neutral probability” default position, the objector would need to give some argument for why the background information would favor ¬H over H. Furthermore, one could argue that if anything the opposite should be done. Hypothesis H has some inferential virtues (things that make an inference good) that go beyond merely entailing E, and thus there are inferential virtues that aren’t captured in Pr(E|H).

One reason to rank H higher than we would otherwise rank it is that it’s part of the nature of rational inquiry to look for explanations for why things exist. To quote what I said in a previous entry:

Here I’ll borrow a bit from philosopher Richard Taylor’s illustration of finding a translucent ball in the woods. “How did it get there?” you ask. I reply, “There is no explanation for it being in the woods; the ball just exists inexplicably.” My response seems less plausible than the idea that there is some explanation for the ball’s existence. What if we enlarged the ball to the size of a car? Same problem: some explanation seems to be needed. How about a city? Same problem. A planet? Same problem. A galaxy? Same problem; increasing the size does nothing to remove the need for an explanation. How about if the ball were as big as the universe? Same problem. All things considered, it seems intuitively plausible that if a contingent thing exists, there is some reason why it exists, since it could have failed to exist.

The universe is contingent, and our default rational preference should be to accept that there is an explanation for its existence. Regarding the translucent ball illustration, Maverick Atheism says:

True enough, increasing the size of the translucent ball does nothing to remove the need for an explanation (let us also assume arguendo that all translucent balls are contingent). Size doesn’t matter, but what does matter is whether the translucent ball existed eternally. It is quite conceivable that there are possible worlds where a translucent orb has existed for all eternity without an external cause. If we had no evidence that the translucent ball began to exist, it would seem at least premature to simply assume it had an external cause

This may be a situation where reasonable people can disagree, but I’m not quite convinced that knowing the translucent ball to be eternal is sufficient to remove the need for an explanation (recall that it wasn’t sufficient in the case of the eternal monument scenario). In any case, suppose also in our eternal translucent ball scenario we had an explanation for its existence that was readily available, fairly straightforward, is the only known viable explanation, and we have no reason to believe the explanation is false. In that case I think the prior probability of there being a sufficient reason for the translucent ball’s existence was fairly good, at least more than 50%.

Similarly, perhaps it is logically possible for the contingent universe to exist eternally and uncaused, and for there to be no explanation for there being something rather than nothing. But it seems more intellectually satisfying to accept that there is an explanation for why there is something rather than nothing, especially if we have an explanation readily available, is the only known viable explanation, and no reason to think the explanation is false. The atheist could argue that we do have reason to think that the theist’s explanation (a transcendent personal cause) is false, but again that would require some kind of argument. In the absence of such an argument, the background information (the nature of rational inquiry, a readily available explanation etc.) if anything favors H over ¬H.

<Prev  |   1   |   2   |   3   |   4   |   Next>

Bayes’ Theorem and the LCA (p.2)

Home  >  Philosophy  >  Atheism/Theism

Bayes’ Theorem and the LCA

<Prev  |   1   |   2   |   3   |   4   |   Next>

Some Preliminaries

The theist can say that the reason why something exists rather than nothing is that God is a necessary being he exists by the necessity of his own nature. An atheist could believe the reason why there is something rather than nothing by being a Platonist, thinking that abstract objects like numbers genuinely exist as nonphysical entities independently of the mind. Yet (in my humble opinion at least) it seems more likely that numbers are more like ideas in the mind and have no more real existence then Sherlock Holmes. If there is no explanation for why something exists (including the necessity of a thing’s nature), then the contingent universe is all there is, and the contingent universe just exists inexplicably without an external cause.

Yet “If there is no explanation for why there is something rather than nothing, then the contingent universe just exists inexplicably” is true then “If the contingent universe has an explanation of its existence, then there is an explanation for why there is something rather than nothing.” To simplify it then I’ll use “Why is there something rather than nothing?” and “Why does the contingent universe exist?” more or less interchangeably, since in all likelihood they probably have the same answer: either (1) it exists inexplicably; or (2) the explanation is a transcendent personal entity that is metaphysically necessary.

Bayes’ Theorem and the LCA

Maverick Atheism doesn’t give any reason to prefer “there is no explanation for why the universe would exist” over “there is an explanation for why the universe would exist.” He seems to argue that “there is an explanation” has only a very slight advantage from the evidence of the universe’s existence. Is he right? Here Bayes’ theorem can be of some help. Suppose we use the following symbols:

• H is the hypothesis that the PSR holds true with respect to the universe (there is an explanation for why it exists; a sufficient reason for its existence).
• ¬H symbolizes that it is not the case that the PSR holds true with respect to the universe.
• E is the evidence of the universe existing.

Basically, ¬H says, “there is no reason for why the universe would exist” in the sense that if the universe does exist, it does so inexplicably with no external cause for its existence. One version of the Bayes’ theorem is the following:

Pr(H|E) =	Pr(H) × Pr(E|H) Pr(E)

What is the likelihood that the universe exists if there is a sufficient reason for its existence? That probability is 100%, so Pr(E|H) = 1. Suppose we have a true agnostic about whether there is an explanation for the universe’s existence (i.e. H and ¬H have equal prior probability) but hadn’t yet taken into account the evidential force E has for H. One might be tempted to set Pr(E) as 0.5, but then we’d get this:

Pr(H|E) =	0.5 × 1 0.5	= 1

As the old saying goes, if it sounds too good to be true, it probably is. There’s something wrong with the above equation; a little math shows that for Pr(E) to be 0.5 here Pr(¬H) must be 0, and that’s mathematically impossible if Pr(H) = 0.5. So what went wrong? Getting the right value for Pr(E) is trickier than one might think. We should be careful not to confuse Pr(E) with Pr(E|¬H); it may be true that in the absence of sufficient reason for the universe’s existence the universe is just as likely to exist as not, but that won’t necessarily hold true for Pr(E), because Pr(E) is equal to the following:

Pr(E) =

Pr(H) × Pr(E|H) + Pr(¬H) × Pr(E|¬H)

So by my lights, using the form of Bayes’ theorem where Pr(E) is on the bottom is not advisable here. With that in mind, another form of Bayes’ theorem is this:

Pr(H|E) =	Pr(H) × Pr(E|H) Pr(H) × Pr(E|H) + Pr(¬H) × Pr(E|¬H)

What about Pr(E|¬H)? We’re looking for the likelihood of E given just ¬H. Without an external cause of the universe to make it exist (and the universe lacking necessary existence) we can estimate the likelihood of it existing given just ¬H as 50%. Suppose one starts out as truly agnostic as to whether there is an explanation for the universe’s existence (i.e. both H and ¬H have a prior probability of 0.5) but had not yet considered the evidential force of the universe’s existence; call this person Al. Agnostic Al is using these probabilities:

• Pr(H) = 0.5
• Pr(E|H) = 1
• Pr(¬H) = 0.5
• Pr(E|¬H) = 0.5

And plugging those values into above formulation of Bayes’ theorem gives us this:

Pr(H|E) =	0.5 × 1 0.5 × 1 + 0.5 × 0.5	=	0.5 0.75	= 2⁄3 ≈ 0.67

So it seems that if one considered H and “there is no reason for why the universe would exist” to be equally likely but hadn’t yet taken into account the evidential force of the universe’s existence for H, one should assign H a probability of about 67% in the absence of further arguments. While that probability isn’t overwhelmingly huge, it’s not exactly negligible either. The existence of the universe would constitute some fairly significant evidence for H, in part because one advantage H has over “there is no reason for why the universe would exist” is that on H it is more likely that the universe would exist. So if in the absence of a sufficient reason “nothing at all exists” is just as likely as “something exists” then this provides a significant advantage for the hypothesis that there is some explanation for why there is something rather than nothing, at least for the aforementioned agnostic Al.

The mathematics is airtight; to reject it one would have to reject the input probabilities. I suspect Pr(E|H) would be pretty uncontroversial given the sense of “sufficient reason” being used here, but the other parts of the probability calculations are more vulnerable.

<Prev  |   1   |   2   |   3   |   4   |   Next>

Bayes’ Theorem and the LCA

Home  >  Philosophy  >  Atheism/Theism

Bayes’ Theorem and the LCA

<Prev  |   1   |   2   |   3   |   4   |   Next>

A while back the Maverick Atheism blog wrote a rebuttal to the Leibnizian Cosmological Argument (LCA), that was in part a rebuttal to my own series on the Leibnizian cosmological argument (though it was also largely a rebuttal to Christian philosopher William Lane Craig, whose form of the LCA I borrowed).

A Brief Recap

For those who aren’t familiar with Bayes’ theorem, I recommend reading this quick introduction to Bayes’ theorem. To recap my series on the LCA a bit, here’s one of the versions I used (one I labeled LCA 1A):

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The universe exists.
3. If the universe does have an explanation for its existence, that explanation is God.
4. Therefore, the universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation for the existence of the universe is God (from 3 and 4).

Premise 1 then is a version of the principle of sufficient reason. Another version of the LCA, one I labeled LCA 3, goes like this, where the contingent universe is the totality of all contingent things:

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The contingent universe exists.
3. If the contingent universe has an explanation for its existence, that explanation is God.
4. Therefore, the contingent universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation of the contingent universe is God (from 3 and 4).

I argued that the contingent universe could have failed to exist, and I also argued that the external cause of the universe would have to be an eternal, transcendent, metaphysically necessary, personal entity. Here’s how it worked: The external cause of the contingent universe could not itself be contingent (since then we wouldn’t have an explanation for the contingent universe) and so must be necessary. What is necessary is also eternal, since at no time and in no circumstances can metaphysically necessary entities fail to exist. Since the physical universe itself is contingent, the external cause would have to be nonphysical, and there are only two candidates in the metaphysical literature for nonphysical entities: abstract objects (like numbers) and unembodied minds (like God). But abstract objects can’t cause anything, so the only known viable explanation would be a nonphysical mind. We thus wind up with an eternal, transcendent, metaphysically necessary, personal entity that is the external cause of the universe. I also argued for a more modest conclusion: that the only known viable explanation for the contingent universe is eternal, transcendent, metaphysically necessary personal entity as the external cause of the universe—and that of course sounds suspiciously like theism, enough to make atheism rather implausible if we knew such an entity exists. Hence this toned down version:

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The contingent universe exists.
3. If the contingent universe has an explanation for its existence, that explanation is is an eternal, transcendent, metaphysically necessary, personal entity.
4. Therefore, the contingent universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation of the contingent universe is an eternal, transcendent, metaphysically necessary, personal entity (from 3 and 4).

God is classically a metaphysically necessary being (i.e. he exists in all possible worlds) and the external cause of the physical universe. But if God is metaphysically necessary, his existence would also explain why there is something rather than nothing.

Maverick Atheism’s Rebuttal

Maverick Atheism attacked the first premise and argued that perhaps the universe does not have an explanation for its existence. The position he put forward:

So we can accept that ceteris paribus a worldview that explains e.g. why there is something rather than nothing is better than one that doesn’t, but given the plausibility of physical reality existing eternally without an external cause, the degree of evidential support this provides is rather small.

There is an element of plausibility in this; most of us can at least envisage the physical universe existing eternally with no external cause. But now consider the following scenario, borrowing largely from my first article on the Leibnizian cosmological argument.

Suppose we humans learned of an eternally existing monument at the center of the universe that says, “I, the Lord thy God, am the sustainer of the universe and have sustained it throughout all eternity” (if questions of different languages bother you, imagine further that it displays this message through a kind of mechanical telepathy such that anybody who looks at the monument sees the message in her own language).

Most of us can at least envisage the monument existing eternally and without an external cause for its existence. Still, somehow the monument existing eternally with no explanation for its existence sounds rather implausible here. Why?

One factor is the likelihood of there being a monument like this in the absence of a sufficient reason for its existence (like some intelligent entity being the external cause of the monument’s existence), and intuitively that likelihood is low. Where H is the hypothesis (of there being a sufficient reason) and E is the evidence (the monument’s existence), we might say that Pr(E|¬H) is very low. If you’ll recall my quick introduction to Bayes’ theorem, you’ll know that a low Pr(E|¬H) is a factor in making Pr(H|E) high.

Is the likelihood of there being something rather than nothing extremely low in the absence of a sufficient reason, an improbability akin to the hypothetical monument existing without a sufficient reason? Maybe not. Still, the question, “Why is there something rather than nothing?” is interesting precisely because (in the absence of a sufficient reason) it seems like it could have been the case that there existed nothing rather than something. Something very similar holds with the contingent universe, since the contingent universe is the totality of contingent things and thus “no contingent thing exists” is no less a real possibility than “nothing at all exists.” Similarly, “no physical thing exists” is no less a real possibility than “nothing at all exists.” In this article, I’ll examine the insights Bayes’ theorem has on this possibility of there being nothing rather than something.

<Prev  |   1   |   2   |   3   |   4   |   Next>

The Leibnizian Cosmological Argument for God (Page 5)

Home  >  Philosophy  >  Atheism/Theism

The Leibnizian Cosmological Argument for God

< Prev   |   1   |   2   |   3   |   4   |   5   |   Next >

LCA 2

Yet another argument:

1. There is an explanation for why there is something rather than nothing.
2. If there is an explanation for why something exists, that explanation is God.
3. Therefore, the explanation for why something exists rather than nothing is God (from 1 and 2).

One could reject premise 2 by being a Platonist, but otherwise we can accept premise 2 for the same sort of reason as we can affirm “If the contingent universe does have an external cause for its existence, that cause is God” if we accept that there are no necessarily existing things with the possible exception of God (apart from God and maybe abstract objects, there doesn’t appear to be any other plausible candidates for necessarily existing things). If God exists he exists necessarily, and if God exists something exists. This would explain why something exists rather than nothing. God also explains why the contingent universe exists and why the physical universe exists. Once again, if the atheist insists that God can’t be used an explanation, we can tone it down and just say that an eternal, transcendent, metaphysically necessary personal entity is the best explanation for why there is something rather than nothing.

One advantage this version of the LCA has is “Why is there something rather than nothing?” more perspicuously requires an explanation. By my lights, the best atheist response to “Why is there something rather than nothing?” (since I wouldn’t be a Platonist if I were an atheist) is “it just exists inexplicably.” All else held constant though, we’re better off with a worldview that gives us an explanation for why there is something rather than nothing as opposed to a worldview that gives us no such explanation.

Conclusion

I’ll summarize and highlight some key points for the series.

Explaining Why the Physical Universe Exists

The first version of the Leibnizian cosmological argument (LCA), what I labeled LCA 1A, goes like this, where premise 1 is a version of the principle of sufficient reason (PSR).

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The universe exists.
3. If the universe does have an explanation for its existence, that explanation is God.
4. Therefore, the universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation for the existence of the universe is God (from 3 and 4).

Premise 3 is plausibly true as a result of “If God does not exist, then the universe has no explanation of its existence” being likely true, since a transcendent personal cause seems to be the only viable explanation for the universe’s existence. With a physical external cause of the universe’s existence being impossible, the universe’s external cause would have to be ethereal and no less strange than God creating the universe. By far the best option for the atheist is to say that universe exists eternally, inexplicably, with no external cause of its existence. “If God does not exist, then the universe has no explanation of its existence” is much more plausible than its denial. But “If God does not exist, then the universe has no explanation of its existence” is logically equivalent to “If the universe has an explanation of its existence, then God exists,” which is almost synonymous with premise 3. Still, if the atheist insists that God cannot be legitimately used as an explanation (for whatever reason) in spite of the strong justification for premise 3, there is the following toned down argument that I labeled LCA 1B:

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The universe exists.
3. If the universe does have an explanation for its existence, that explanation is a transcendent personal cause.
4. Therefore, the universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation for the existence of the universe is a transcendent personal cause (from 3 and 4).

The physical universe having a transcendent personal cause still makes atheism less plausible.

By my lights the weakest part of the LCA is the PSR, such that it is the premise I would reject if I were an atheist. The argument crucially hinges on the universe having an explanation of its existence, but there is good reason to accept that there is an explanation for the existence of the universe. The justification offered:

1. The translucent ball in the woods illustration. Increasing the size of the ball doesn’t remove the need for an explanation. This helps to illustrate that it is rational to accept that there are explanations for the existence of things, at least when we have no reason to think that an explanation doesn’t exist (if most of the universe were merely a translucent ball, it seems we’d still need an explanation for the ball’s existence).
2. The nature of rational inquiry. It’s the nature of rational inquiry to look for explanations for why things exist. We seek explanations for the existence of humans, of planets, of stars, and of galaxies. Avoiding all that and saying, “It all just exists inexplicably” would cripple science. And if we are rational to accept that there are explanations for the existence of planets, stars, and galaxies, why not also accept that there is an explanation for the existence of the physical universe? Simply not liking the only viable explanation for the universe’s existence isn’t a good enough reason. The rational thing to do is to accept that there are explanations for the existence of things if we don’t have good reason to believe otherwise, especially if we have an explanation readily available and no evidence for the explanation being false (e.g. believing that the cosmic microwave background radiation just exists inexplicably is less rational than accepting that the big bang theory explains it).
3. If the shoe were on the other foot… If we had an explanation for the existence of the physical universe that devastated theism (imagine that the best explanation for the physical universe’s existence required that God does not exist) and it was the only viable explanation, and a theist gave a “Maybe there’s just no explanation” response, atheists would argue that the response is just an attempt to avoid a serious intellectual problem for theism, and that the rational thing to do is to accept that there is a an explanation for the existence of the physical universe if we don’t have good reason to believe otherwise. And such atheists would be right! But if that is true, rationality dictates that we be consistent and acknowledge that the best (and apparently the only viable) explanation for the existence of the universe being a transcendent personal cause is a serious intellectual problem for atheism, and that we should accept that there is an explanation for the existence of the universe if we don’t have good reason to think otherwise.

One could say that the universe is eternal, but it’s clear that something being eternal doesn’t necessarily remove the need for an explanation. For example, we can conceive of a three-dimensional hologram projection that exists eternally and is also eternally sustained by a hologram projector. With that in mind, if there is some thing X that meets the following conditions...

1. X is eternal but contingent (it could have failed to exist).
2. There is an explanation for why X exists.
3. It is the only explanation of X’s existence that is a live option.
4. There is no reason to believe that this explanation for X’s existence is false.

…then it seems we should accept that explanation for X if we have no good reason not to. It’s also good to remember the three reasons above for believing that the rational thing to do is to accept that the universe has an explanation of its existence if we have no good reason to think otherwise. In the “shoe on the other foot” case for example, suppose we had an explanation for the physical universe’s existence that was devastating to theism and the explanation met conditions 1 through 4 (it explains why the universe exists, there is no other viable explanation etc.). Couldn’t the atheist justifiably accept this explanation as evidence against theism? If so, then we should recognize that the only viable explanation for the physical universe’s existence being a transcendent personal cause poses a serious intellectual problem for atheism.

Even if the theist grants that maybe not every eternal contingent thing has an explanation of its existence, all things considered it seems the theist is on good grounds to say that at least the universe has an explanation of its existence, in which case the theist can use this version of the LCA that I labelled LCA 1C:

1. If the universe exists it has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The universe exists.
3. If the universe does have an explanation for its existence, that explanation is a transcendent personal cause.
4. Therefore, the universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation for the existence of the universe is a transcendent personal cause (from 3 and 4).

This still yields a conclusion that, if true, makes atheism considerably less plausible.

The Argument from Contingency

One form of an argument from contingency (what was called LCA 3) goes as follows:

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The contingent universe exists.
3. If the contingent universe has an explanation for its existence, that explanation is God.
4. Therefore, the contingent universe has an explanation of its existence (from 1 and 2).
5. Therefore, the external cause of the contingent universe is God (from 3 and 4).

To summarize the justification for premise 3: the contingent universe does not exist necessarily, i.e. there is a possible world where no contingent thing exists. Thus the contingent universe does not exist by the necessity of its own nature and (due to premise 1) has an external cause. All of physical reality is contingent, and since the physical universe is a subset of the contingent universe, the external cause of the contingent universe would have to be nonphysical. We can then employ the same sort of reasoning in LCA 1 to conclude that the nonphysical external cause of the contingent universe is a transcendent personal cause. Since we’re looking for an external cause of the contingent universe (i.e. the totality of contingent things), that which is the external cause of the contingent universe cannot itself be contingent but must be metaphysically necessary. So the transcendent personal entity that is the external cause of the contingent universe is metaphysically necessary. What is metaphysically necessary is also eternal, since at no times and in no circumstances can metaphysically necessary entities fail to exist. So the transcendent, metaphysically necessary, personal entity that is the external cause of the contingent universe is also eternal. We thus end up with an eternal, transcendent, metaphysically necessary, personal entity that is the external cause of the contingent universe if the contingent universe has an explanation of its existence. Consequently, “If God does not exist, then the contingent universe has no explanation of its existence” is very likely true, and since “If God does not exist, then the contingent universe has no explanation of its existence” is logically equivalent to “If the contingent universe has an explanation of its existence, then God exists” we have strong reason to believe that premise 3 is true.

As before, if the atheist for whatever reason insists that God can’t be used as an explanation, then we can construct a tone downed version of the argument.

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The contingent universe exists.
3. If the contingent universe has an explanation for its existence, that explanation is is an eternal, transcendent, metaphysically necessary, personal entity.
4. Therefore, the contingent universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation of the contingent universe is an eternal, transcendent, metaphysically necessary, personal entity (from 3 and 4).

Arguably, any atheism that accepts the existence of an eternal, transcendent, metaphysically necessary, personal entity that is the cause of the universe would not be worthy of the name “atheism.”

The question “Why is there something rather than nothing?” is one of the most fundamental questions in philosophy. The atheist can say, “Platonism is true and abstract objects exist necessarily, and if abstract objects exist something exists.” But if the atheist is not a Platonist, it seems that atheism cannot offer a viable explanation for why there is something rather than nothing whereas theism does. Moreover, even if we were to grant Platonism, there is a “Why does the contingent universe exist?” question that Platonism cannot answer (since abstract objects cannot cause anything) and we end up with an eternal, transcendent, metaphysically necessary, personal entity causing the universe. This is enough to make atheism less plausible.

While one could believe that the transcendent personal cause for the physical universe is different from the transcendent personal cause of the contingent universe, Ockham’s razor suggests we not multiply explanatory entities unnecessarily and it is simpler to posit the same transcendent personal cause for both the physical and contingent universe (I suspect there is extremely large overlap between the physical universe and the contingent universe anyway). Even apart from that, if we justifiably believe that there is a transcendent personal cause of the physical universe and a transcendent personal cause of the contingent universe, this is enough to be intellectually dangerous to atheism.

In any case, God (or at least an eternal, transcendent, metaphysically necessary, personal entity as the external cause of the physical/contingent universe) explains why there is something rather than nothing, why the physical universe exists, and why the contingent universe exists. If nothing else, theism has a certain explanatory scope for things that the atheist has no satisfactory explanation for (assuming the atheist is unwilling to concede e.g. a transcendent personal cause of the physical universe).

< Prev   |   1   |   2   |   3   |   4   |   5   |   Next >



Comment on this article

The Leibnizian Cosmological Argument for God (Page 4)

Home  >  Philosophy  >  Atheism/Theism

The Leibnizian Cosmological Argument for God

< Prev   |   1   |   2   |   3   |   4   |   5   |   Next >

From Before

Some forms the LCA can take:

1. The argument that asks, “Why does the physical universe exist?” and offers theism as an explanation.
2. The argument that asks “Why is there something rather than nothing?” and offers theism as an explanation. One weakness: Platonists believe that abstract objects (like numbers) exist independently of the mind and have necessary existence, and so Platonists won’t see the need for God as an explanation because Platonic abstract objects exist by the necessity of their own nature. If you’re not a Platonist though, this is potentially a good argument because “Why is there something rather than nothing?” is an excellent question and it seems to be the sort of thing that we should look for an explanation for.
3. The argument that asks, “Why do contingent things exist?” and offers theism as an explanation. This bypasses the problem of Platonism because abstract objects (like the number six) can’t cause anything, including contingent objects. This type of argument is also called “the argument from contingency.”

Let’s label the above three LCA arguments LCA 1, LCA 2, and LCA 3, respectively. In part 1 of the series I argued for a few versions of LCA 1, and in so doing I also argued for a form of the principle of sufficient reason (viz. “Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause”), an important and controversial part of the LCA. In this blog entry I’ll deal with the other two LCA varieties.

LCA 3

Yeah, I’m going kind of out of order, but that’s what you get when you read an article written by a maverick Christian (sometimes). For LCA 3 we can use the same sort of reasoning as LCA 1 except we replace the “physical universe” with the “totality of contingent things,” where we can call the “totality of contingent things” the “contingent universe” (if you’re wondering what the difference is between the contingent universe and the physical universe, the contingent universe would include contingent nonphysical entities like angels and souls if they exist). LCA 3 suggests that it’s possible for the contingent universe to not exist, i.e. that there is a possible worlds where no contingent thing exists. Thus, the contingent universe does not exist by the necessity of its own nature. We could justify that assertion with an argument from subtraction; upon reflection it seems there is a possible world where only a thousand contingent things exist, and it seems there is a possible world where only fifty contingent things exist etc. all the way down to zero contingent things existing. If nothing else, we can point out that it’s possible for the contingent universe to have had a different collection of contingent things it now has, similar to how our own physical universe could have had a different collection of fundamental physical units.

Beyond the argument from subtraction, there is one other thing to consider. It seems clear that there is no physical thing that exists necessarily, but one could propose that while there is no creative force that exists necessarily (like God), in all possible worlds there is a contingent thing. That is, it is necessary that some contingent thing or other exists, but there is no physical (or contingent) thing in particular that exists necessarily. One problem with this view: why is it that a contingent thing exists in every possible world? After all, on this view there’s no necessarily existing creative force to bring them about in every possible world. The proponent of this view would have to say that it’s inexplicable; it just happens to be the case that in every possible world there is a contingent thing. But the number of possible worlds is quite literally infinite; the odds that by chance there just happens to be a contingent thing in every possible world is infinitesimally small. That there is a possible world in which there is no contingent thing seems much more plausible than its denial.

Bringing out the whole argument more explicitly:

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The contingent universe exists.
3. If the contingent universe has an explanation for its existence, that explanation is God.
4. Therefore, the contingent universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation of the contingent universe is God (from 3 and 4).

The physical universe (all of physical reality) is contingent, and since the physical universe is a subset of the contingent universe, the external cause of the contingent universe would have to be nonphysical. We can then employ the same sort of reasoning in LCA 1 to conclude that the nonphysical external cause of the contingent universe is a transcendent personal cause.

Further reasoning shows that the transcendent personal cause of the contingent universe is also metaphysically necessary (it exists in all possible worlds and cannot fail to exist) and eternal. If it’s possible that no contingent thing exist, you can’t sensibly appeal to a contingent thing to explain the contingent universe, because any contingent thing is part of the contingent universe, so it wouldn’t be an explanation for why the contingent universe exists as opposed to no contingent things existing. Similarly, one can’t say that the physical universe causing itself (as if by time travel) gives us an adequate explanation, because the entire causal-loop universe would (as a contingent thing) require explanation for its existence. But if no contingent thing can explain the existence of the contingent universe, the only hope left is to appeal to a necessarily existing entity. But then the explanation for the universe’s existence is also eternal, since at no time and in no circumstances can necessarily existing entities fail to exist. So we have an eternal, transcendent, metaphysically necessary, personal entity that is the external cause of the contingent universe. This sounds even more like God. Similar to the case of LCA 1, if the atheist insists that we can’t use God as any type of explanation (for whatever reason) or does not like God being a part of the third premise etc., we can tone down the argument a bit as follows:

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The contingent universe exists.
3. If the contingent universe has an explanation for its existence, that explanation is is an eternal, transcendent, metaphysically necessary, personal entity.
4. Therefore, the contingent universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation of the contingent universe is an eternal, transcendent, metaphysically necessary, personal entity (from 3 and 4).

Once one grants the existence of an eternal, transcendent, metaphysically necessary personal entity as the cause of the universe, atheism becomes much less plausible to say the least. Arguably, any atheism that accepts the existence of an eternal, transcendent, metaphysically necessary personal entity that is the cause of the universe would not be worthy of the name “atheism.”

< Prev   |   1   |   2   |   3   |   4   |   5   |   Next >



Comment on this article

The Leibnizian Cosmological Argument for God (Page 3)

Home  >  Philosophy  >  Atheism/Theism

The Leibnizian Cosmological Argument for God

< Prev   |   1   |   2   |   3   |   4   |   5   |   Next >

The Argument (LCA 1A)

1. Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The universe exists.
3. If the universe does have an explanation for its existence, that explanation is God.
4. Therefore, the universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation for the existence of the universe is God (from 3 and 4).

Justifying Premise 1: the PSR

This brings us to the premise that’s the most controversial: premise 1. Why think that “Everything that exists has an explanation of its existence, either in the necessity of its own nature or an external cause”? Here I’ll borrow a bit from philosopher Richard Taylor’s illustration of finding a translucent ball in the woods. “How did it get there?” you ask. I reply, “There is no explanation for it being in the woods; the ball just exists inexplicably.” My response seems less plausible than the idea that there is some explanation for the ball’s existence. What if we enlarged the ball to the size of a car? Same problem: some explanation seems to be needed. How about a city? Same problem. A planet? Same problem. A galaxy? Same problem; increasing the size does nothing to remove the need for an explanation. How about if the ball were as big as the universe? Same problem. All things considered, it seems intuitively plausible that if a contingent thing exists, there is some reason why it exists, since it could have failed to exist.

One way a thing can have an explanation for its existence is to exist by the necessity of its own nature, but that isn’t an option for contingent things. The other way to explain why something exists is by reference to an external cause. But as far as the PSR is concerned, a thing that has an external cause as its explanation need not have begun to exist. For example, one idea is that the universe’s existence is being eternally sustained by God, similar to an eternal flutist eternally sustaining a note of music; God is the ground of all being and if God were to cease existing so would the universe. So the PSR does not require that contingent things begin to exist. That said, with the finite age of the known physical universe (among other considerations) it seems more likely to me that God created the universe as opposed to (merely) sustaining it in being.

Why do we need an external cause? Why not have an explanation from within, especially if the universe is infinitely old? While I think the universe is most likely of a finite age, not everybody agrees, especially atheists. With an infinitely old universe, we could conceive of each part of an infinitely long causal chain having an explanation for its existence, and one idea is that if we explain each individual element in the physical universe, then we explain the whole.

But this thinking commits the fallacy of composition, unjustifiably asserting something is true for the whole because it is true for the parts, e.g. because each part of an elephant is light in weight, therefore the whole elephant is light in weight. The fallacy in the case of explaining the universe reveals itself by considering the following scenario, borrowing largely from Leibniz’s illustration of copied geometry books. Suppose there have always been geometry books and that each geometry book has been copied from a previous book. So throughout the infinite past, there have been an infinite series of geometry books, each one copied from its predecessor. Although this is an explanation for each geometry book, it does not explain why we have an infinite series of geometry books rather than e.g. an infinite series of books on propositional logic, since that series of books could have been copied from eternity past as well, if geometry books could have. Nor does it explain why there is an infinite series of geometry books rather than no infinite series of books at all. Consequently, it does not explain the existence of the infinite series as a whole, even though it explains the existence of each individual book. That sort of thinking behind the infinite series of geometry books also applies to a physical universe with an infinitely long causal chain. Even though we have an explanation for each link in the chain, we can still ask why this infinite series exists rather than some other infinite series, and we can still ask why there exists an infinite series rather than no series at all. Explaining each part does not entail explaining the whole, and to think otherwise commits the fallacy of composition.

What about a causal-loop universe? One could argue that the universe has an internal cause of its existence in the sense of the universe causing itself, but that idea is metaphysically incoherent; for the universe to cause itself it would have to already exist. I know, time travel is a time-honored tradition of science fiction, but in the real world an agent going back in time to affect its own existence (say, a robot named Bob existing because it goes back in time to create itself) faces severe if not fatal problems (e.g. if such a thing were possible, it seems the aforementioned Bob the robot could also have gone back in time to destroy its younger self, thereby entailing that it doesn’t go back in time to destroy its younger self, thereby producing a self-contradictory state of affairs).

Still, suppose we believe that a causal-loop universe is metaphysically coherent. The causal-loop universe would itself be contingent and could have failed to exist, and the sort of problems affecting the infinitely causal chain afflict the causal-loop universe, in part because a causal-loop universe just is a specialized instance of an infinite past (albeit one that loops forever rather than a more linear infinite past). We can still ask why this particular circular causal chain exists rather than some other circular chain, and we can still ask why a circular causal chain exists rather than there being no such chain. Pointing to any component of the causal-loop universe (say, a time-travelling cause) won’t work to explain the universe’s existence because any such component is part of the very thing to be explained. It would be like trying to explain the existence of a circularly moving river (if such a thing were possible) by pointing to one half of the river in which water flows from that half to the other half of the river; this would do nothing to explain why the river as a whole exists rather than not (e.g. it wouldn’t explain why the river as a whole has water rather than there being no water to circulate). Similarly, pointing to any causal-flowing segment of a circularly-causal universe wouldn’t explain why the causal-loop universe as a whole exists rather than not.

Another way to look at premise 1 is that it’s the nature of rational inquiry to look for explanations for why things exist. We seek explanations for the existence of humans, of planets, of stars, and of galaxies. Avoiding all that and saying, “It all just exists inexplicably” would cripple science.

Challenging the PSR

Even if it is the nature of rational inquiry to look for explanations, a critic could say that this methodological aim to look for explanations doesn’t entail that explanations will always be found. A gold prospector might have the attitude of “Always look for gold” but that method doesn’t entail she will always find gold. So maybe not everything that exists has an explanation for its existence.

Maybe that’s true. In fact, maybe some things we think have explanations don’t have explanations at all. It’s logically possible (in the sense of not being self-contradictory) that the big bang theory is false and that the things that the big bang theory explains, like the cosmic microwave background radiation, simply exist with no explanation for their existence.

Still, that doesn’t seem to be the most rational way to go. The same holds true for a giant translucent ball (no matter how large it is). We should not exempt the universe from requiring an explanation if we have no good reason to do so, since it seems more rational to accept that there are explanations for the existence of things if we don’t have good reason to believe otherwise, especially if we have an explanation readily available and no evidence for the explanation being false. In regards to finding an explanation for the universe’s existence, if the only reason one rejects the proposed explanation in favor of “there is no explanation” is that one just doesn’t like the proposed explanation very much, it doesn’t seem like such a person has a good enough reason (imagine if someone rejected the big bang theory for that reason!). One could argue that, all things considered (the nature of rational inquiry etc.) we should accept PSR unless we have good reason to believe that it is false, including when it comes to the existence of the physical universe.

Another consideration is to imagine the shoe being on the other foot; if the best known explanation for the existence of the physical universe were devastating to theism instead of devastating to atheism, I suspect atheists would criticize a theist’s “the universe has no explanation” response, and they would be right to do so. The rational thing to do is to accept that there is an explanation for the existence of the universe if we don’t have good reason to think otherwise.

Do we have such a reason? Here’s the best atheist position I can think of. While contingent things that begin to exist require an explanation of their existence via an external cause, contingent things that exist eternally don’t necessarily have external causes and thus don’t necessarily require an explanation of their existence. Such contingent things exist eternally and inexplicably. The atheist can argue that the physical universe fits this category: it is contingent but eternal and doesn’t have an explanation of its existence.

The first thing to say is that it isn’t necessarily the case that if a contingent thing exists eternally that no explanation for its existence is needed. For example, suppose we humans learned of an eternally existing monument at the center of the universe that says, “I, the Lord thy God, am the sustainer of the universe and have sustained it throughout all eternity” (if questions of different languages bother you, imagine further that it displays this message through a kind of mechanical telepathy such that anybody who looks at the monument sees the message in her own language). A response like, “Well, the monument existed eternally, so no explanation is needed for why this monument exists” doesn’t seem convincing. Or to use a more decidedly nontheistic example, imagine a three-dimensional hologram projection that exists eternally and is also eternally sustained by a hologram projector. Even though the hologram exists eternally, we have an explanation for the hologram’s eternal existence. The hologram is contingent and it could have failed to exist, and there is an explanation readily available for why it exists rather than it not existing. With that in mind, suppose some contingent thing X meets the following conditions:

1. X is eternal but contingent (it could have failed to exist).
2. There is an explanation for why X exists .
3. It is the only explanation of X’s existence that is a live option.
4. There is no reason to believe that this explanation for X’s existence is false.

I think that if we know that all four conditions are met for thing X, then we should accept that explanation for X if we have no good reason not to. In considering these conditions it might also help to envisage the shoe being on the other foot. Suppose we had an explanation for the physical universe’s existence that was devastating to theism and the explanation met conditions 1 through 4 (it explains why the universe exists, there is no other viable explanation etc.). I have a hard time believing that atheists wouldn’t use this devastating-to-theism explanation as evidence against theism. Moreover, it seems they would be right to do so if their explanation for why the universe exists rather than not is the only viable explanation, there is no evidence against the explanation etc. But then rationality dictates we be consistent and recognize that a transcendent personal cause meeting these conditions poses a serious intellectual problem for atheism.

It’s possible that the atheist thinks there is a good reason to believe the transcendent personal cause explanation is false and thus that condition 4 is not met, though I have yet to see such a reason. In any case, it seems clear that for the atheist to rationally reject the explanation, some good reason will need to be given, i.e. the ball is in the atheist’s court. Such atheists don’t have to swing at the ball, but if they don’t, they’ll lose the game.

At the end of the day, the theist can grant for sake of argument that maybe some eternal contingent things don’t require explanations for their existence and still argue that all things considered (e.g. the four conditions mentioned earlier regarding eternal contingent things, and what would be rational to do if the shoe were on the other foot) we are rational to accept that the universe has an explanation of its existence, giving us this version of the LCA (call it LCA 1C):

1. If the universe exists it has an explanation of its existence, either in the necessity of its own nature or an external cause.
2. The universe exists.
3. If the universe does have an explanation for its existence, that explanation is a transcendent personal cause.
4. Therefore, the universe has an explanation of its existence (from 1 and 2).
5. Therefore, the explanation for the existence of the universe is a transcendent personal cause (from 3 and 4).

If all three premises are rational and justified, we still have a conclusion that makes atheism considerably less plausible even with the weakened version of premise 1.

< Prev   |   1   |   2   |   3   |   4   |   5   |   Next >



Comment on this article