Saturday, January 31, 2015

FTA part 2: General questions for Aron (part of the Aron Series)

Aron, how are you doing? I’m glad to hear from you again! I hope you continue to think deeply about these questions.

To be honest, I didn't realize that I was going against what Larry believed about using epistemic probabilities and such. At any rate, I am glad we came to some agreement about how TAG could possibly be used in an argument, even if we still don’t agree on whether certainty in TAG renders evidence for God useless.

Hey, but now that we've come to some sort of conclusion, it sounds like you want to switch gears and go more in-depth into the fine tuning? Would that be correct? I’m interested in doing that. I find the fine tuning argument fascinating, and it is definitely one of the arguments that first opened the door to my skeptical way of thinking to allow me to entertain the possibility that God exists.

But before we get too in-depth with this argument, and I see that you have put forth a couple challenges to it, I was wondering if you’d answer a couple of questions? The reason why is I don’t know you very well. (Maybe Larry does, but I don’t!)

First, I am assuming you are not a believer in Jesus in the classical Christian sense. Is that right? Did you ever at one point consider yourself to be a Christian?

Assuming your answer to the first question is, “No, I am not a believer,” what is your interest in Ratio Christi?

What is your favorite argument in favor of the existence of God?

What is your favorite argument against the existence of God?

A lot of atheists these days take a very hard scientistic stance, in which the only allowable evidence in discussions about whether God exists is evidence that can be tested scientifically. I am assuming that would not be your stance, given how into the TAG you got, but I just wanted to make sure.

Thanks a bunch for humoring me on answering these questions. The reason why I think they’re important is because knowing your background might help us avoid talking past each other. To be fair, I will give you my answers.

I am a believer, but I grew up atheist. My favorite argument in favor of the existence of God is...well, it’s hard to pin one down. I've switched back and forth over the years, but as I said, the fine tuning argument was one of the first that I heard and it really went along way to convincing me to go from being an atheist to theist. For this reason, I am really passionate about apologetics, which is why I am passionate about Ratio Christi.

My favorite argument for atheism is the problem of evil, as well as the horrific events in the OT as evidence against Yahweh being perfectly good; those two are very tough problems for the Christian.

I am clearly not a proponent of scientism, although I am a scientist.

FTA part 1: Aron challenges that the probability if fine tuning is low (part of the Aron Series)

Aron wrote:
I like your cumulative case method because it looks like you're using Jeffrey conditioning. The probability of G in light of TAGs uncertain status=P(G/TAG)xP(TAG)+P(G/~TAG)xP(~TAG). The left side would be 1x.6, and the right side would be .4 multiplied by whatever you think P(G) is given all the other evidence. In this case, you can use TAG along with evidential arguments. That's why I think the Bayesian approach is best, bc it can let you do stuff that you couldn't do if you were offering TAG as a proof. I don't think Larry would be open to this approach though.

My initial argument was offered against someone who uses TAG as a deductive argument, so my point still holds in that context. I think you offer a good way to sidestep the problem. But even with the method you offer, my main point still stands: evidential arguments can only make a contribution if you're open to the possibility that TAG is wrong.

About fine tuning. I agree for the most part. There are a few ways I could push back. For what it's worth, there's a long tradition, going back to at least Spinoza, of arguing that P(FT/G) is either 0 or near 0. (Spinoza obviously didn't talk about fine tuning per se, but he argued that God wouldn't/couldn't create a universe bc he'd have no reason to do so, given his lack of wants/needs).

Also, be careful with P(FT/~G). The fine tuning data doesn't say this number is small, it says that the life permitting range of values is small. If someone says a constant is fine tuned to one part in 10 billion, they aren't saying that there is a 1/10 billion chance that the constant would have that value. Instead, they are just saying that if the value of the constant were changed by one ten billionth of a percent, then life couldn't exist. Claims about fine tuning are about the narrowness of the life permitting range of values a constant could take. Additional argumentation is needed to show that its improbable that a constant would take a value in that range. To say that P(FT/~G) is low, you need to make some philosophical assumptions, such as the adoption of the principle of indifference and the rejection of the axiom of countable additivity.

Aron and the transcendental argument (part of the Aron Series)

Please see below for my discussion with Aron about the transcendental argument for God's existence (TAG).  I apologize for the abrupt beginning, but I jumped into the conversation in medias res, as it were.  And unfortunately I have no way of retrieving Aron's earliest points in the argument, including his formal argument points (1-8).

For links to the full series, see here.


Greg Reeves wrote:
As a scientist/engineer and not a philosopher, I am also not the best qualified, but with that disclaimer... If Ron is right that the possibility of having evidence against God is necessary for the design argument to succeed, then yes indeed the design argument fails. And he would be absolutely right about the first line of argumentation.

But even if we grant him that needing the possibility of having evidence against God is required for successful evidential arguments against God, Argument 1 is a paradox, not a contradiction, because he is leaving out crucial qualifiers in statements (1) and (8).

When he says "the design argument succeeds" he should be saying "were logic possible without God, the design argument succeeds" (a true statement).

At the end, when he says "the design argument fails" it is instead "now that we have proven that God is necessary for logic to be possible, and the design argument rests on the operation of logic, then the design argument fails (in that it cannot not be true)". This last statement does not contradict the previous statement; they are different statements and he is guilty of equivocation in the word "fails".
In other words, the design argument goes through under certain premises, and does not under others. So what? What he has shown is that if TAG is true, the design argument fails, but only because God is proven rather than uncertain; while if TAG is false, then the design argument succeeds and therefore God is a high probability. In other words, he has shown that God is either a certainty or a highly probable being.

What about his second line of argumentation? Equivocation again. If he is granting TAG in the second argument, then not only is (1) true, but the laws of logic would not hold were God to not exist. Therefore, instead of (3) he should be saying "The fine tuning argument is a successful evidential argument for God if logic is possible without God (assumption)." Instead of (4) it would be "Therefore, God would exist even if logic were possible without God." Then (6) would become, "But there could be theoretical evidence against God, given the success of the fine tuning argument, were logic to be possible without God." And (7) would be a near-tautology: "Therefore, there is no being whose nature is the foundation of logic were logic possible without God." Then (8) Therefore, God would not exist were logic possible without God." Finally, (9) "Therefore, logic is impossible without God." Which is where you began anyway since he started by granting TAG.

We should all (myself included) be very careful about his hidden premises/equivocation.

What about his proof that starts out with "If there is a true statement that takes the form 'there is evidence for x', then it confirms theism?" In this proof, I think he is starting with the assumption that TAG is true, meaning the laws of logic depend on God. But this proof clearly has a problem with it...I am probably not getting my terms 100% correct, but I think Ron is conflating epistemic probability (what we think is true based on the evidence) from ontological probability (what actually IS). If we are uncertain that God exists, then based on evidence, we can epistemically put a probability on our belief (crudely). Such and such evidence favors the interpretation that God exists. Other evidence may favor atheism. But in an uncertain world you can truly have evidence that favors a proposition that is untrue. Therefore, having evidence for a proposition does not make that proposition true...all it does is make the statement "there is evidence for this proposition" true.

But if God really does exist, then atheism (here I am using it as the state of affairs in which no God exists) is ontologically untrue. No matter how much evidence you may say there is for atheism, if God does in fact exist that makes atheism untrue. So the way in which he wants "there is evidence for atheism" to mean atheism is true is just a false maneuver. So let's update his actual argument with this in mind:

1. If there is a true statement that takes the form “there is evidence for x”, then it confirms theism (because of TAG).
2. The statement “there is evidence for atheism” is a statement that takes the form “there is evidence for x”.
3. Therefore, if the statement “there is evidence for atheism” is true, then it confirms theism (which has already been proven because TAG was granted).
4. If the statement “there is evidence for atheism” is true, then it, in principle, challenges theism because it means evidence against theism exists.
5. Therefore, if the statement “there is evidence for atheism” is true, then it both confirms (100%) and challenges (makes you wonder about) theism.
6. If the truth of the statement “there is evidence for atheism” both confirms and challenges theism, then the conclusion that one may draw from the evidence for atheism (ie, that atheism is true) statement is necessarily false. In other words, even though there is evidence for atheism, that evidence does not go through.
7. Therefore, the statement “there is evidence for atheism” if true, may lead you to a false conclusion if you don't realize that such a logically true statement confirms theism (100%) under TAG.
8. Therefore, Premise 1 necessarily leads to the conclusion that while there can be evidence for atheism, atheism is still false.

So in summary, atheism can have evidence for it, but *if TAG is granted* then atheism is false, so evidence for atheism is incorrect. But if TAG is not granted, then you can marshal evidence all you want and we'll see which one stacks up better. Ultimately the existence of the laws of logic have a more comfortable fit in a theistic worldview rather than an atheistic one, and the atheist is left with the uncomfortable task of explaining their existence.


Aron wrote:
Greg, in your first post, what exactly do you mean with this paragraph: "In other wordsthe design argument goes through under certain premises, and does not under others. So what? What he has shown is that if TAG is true, the design argument fails, but only because God is proven rather than uncertain; while if TAG is false, then the design argument succeeds and therefore God is a high probability. In other words, he has shown that God is either a certainty or a highly probable being." My point was to show that, under the assumptions of TAG, the design argument fails, and under the assumptions of the design argument, TAG fails. Are you agreeing with me that the success of one entails the failure of the other?

I'm talking about epistemic probability here.

When I talk about evidence, I mean that some fact makes a hypothesis more epistemically likely than it would have been without it. E is evidence if P(H/E)>P(H). This condition will be met if P(E/H)>P(E/~H).

You're absolutely right that there can be evidence against a true hypothesis (i.e., evidence that lowers it's epistemic probability). For example, if I were framed for murder and the weapon was planted in my sock drawer, this would increase the epistemically probability in the detective's mind that I was guilty. This is despite the fact that, ontologically, the probability that I'm guilty is 0.

So there is no doubt that evidence can pull in different directions epistemically. Some evidence may suggest I'm the killer, and other evidence may suggest I'm innocent. However, no single piece of evidence can simultaneously confirm and challenge a hypothesis. This would mean that for that particular evidence E, P(E/H)>P(E/~H) and P(E/H)
P(H/E) and P(H)

So imagine some fact F raises the epistemic probability of atheism. This would mean P(F/atheism)>P(F/theism), and therefore P(atheism/F)>P(atheism). But, if we think that logic presupposes theism, then we should think every fact about the world increases the epistemic probability of theism to 100% (this is bc in order for there to be facts, laws like the law of identity and non contradiction must apply). This would mean that while F raises the epistemic probability of atheism, it must do the same for theism. Contradiction.

Thus, while it is true that we can have evidence against a true hypothesis, this is only true when that hypothesis is not the foundation of logic itself. If you want to admit the possibility of evidence against theism, you need to drop the premise that logic depends on God.


Greg Reeves wrote:
Aron, sorry that I did not know you had responded to me.  I guess I didn't get any update saying so.  Like I said originally, I am a scientist and engineer, so you have to take what I say with a grain of salt about these matters.

What I meant in the first paragraph is that under some conditions, TAG goes through, and under others DAG (design) goes through.  Meaning, if you accept TAG, and you condition your DAG argument on TAG, then you end up with an inescapable 100% probability for God, because you have already conditioned your DAG argument on the background that God exists.  So, yes I do agree with you that the success of TAG entails the failure of DAG *only if you are correct that* and *only in the sense that* you must have the possibility of some evidence contrary to an argument to make the argument successful.  But I did say up front that I do not necessarily accept that. But again, even if I did, then DAG would only fail in that sense, but would not fail in the sense that God has been proven to not exist.  It seems to be only a technicality.

But I definitely could be wrong about that, so let's explore your suggestion about probabilities.  Let me make sure I am understanding you correctly.  You are concerned that if you have a piece of evidence that increases your epistemic probability for atheism, then under TAG it also simultaneously decreases the evidence for atheism (because any logical construct, if it exists, on TAG, proves theism).  You are then worried that if you accept TAG then you get a logical contradiction.  Therefore, TAG cannot be true.

Problem is, since we are dealing with epistemic probability, you have to be *very careful* because epistemic probability can be very tricky.  You can end up sneaking all sorts of stuff in the back door.  Here is where I think you are going wrong.  I will try to parse my answer in the context of your previous paragraph that started with "So imaging some fact F...":

So imagine some fact F raises the epistemic probability of atheism if you do not accept TAG. This would mean P(F/atheism)>P(F/theism), and therefore P(atheism/F)>P(atheism). But, if we think that logic presupposes theism, in other words, if we then condition our probabilities on TAG, then we should think every fact about the world increases the epistemic probability of theism to 100% (this is bc in order for there to be facts, laws like the law of identity and non contradiction must apply). This would mean P(atheism/F & TAG)

Remember, formally the law of non-contradiction says both A and ~A cannot hold at the same time, in the same way, and *under the same circumstances*.  Conditioning on TAG completely changes your circumstances.  So we are back to what I said in my original post.  It depends on your premises.  You change your premises and then of course your conclusions can change.  If logic were possible without God (ie, you don't condition on TAG), then you could use logic to try to prove atheism.  If indeed TAG is true, and you condition on it, then any piece of evidence that you previously used in support of atheism when you did not condition on TAG is no longer in support of atheism.  If you wish, I could write out a full Bayesian analysis on this, but I get the feeling that most readers of this forum would not benefit from it.


Aron wrote:
I don't think we disagree about anything. Once you have come to accept TAG and incorporated it into your background knowledge, then any probability assessments you make will be conditioned on TAG. And you agree that if we condition on TAG, there could never be evidence against theism. But if this is the case, then there could never be evidence for theism either, so the design argument won't work. You seem to agree with this, but think it's "trivial." The reason I don't think it is trivial is that it forces people to make a choice. If you think TAG is true, then you can't think that biological complexity makes theism more likely than it would otherwise be. And if you think biological complexity lends support to theism - i.e. Pr(theism/biology)>Pr(theism) - then you can't have TAG in your background knowledge. I have seen people make cumulative cases that include both arguments, and I don't think this is an option. You can't simultaneously believe that both arguments are sound.

Greg, I wouldn't mind seeing your Bayesian analysis of Dawkins.


Greg Reeves wrote:
Aron, I am glad we aren't disagreeing then, but I do want to take you to task a little bit because I was primarily responding to how you said these things were *contradictions*.  It is not a formal contradiction because you are either conditioning on TAG or not, and that changes your outcome.

But I like how you want to be very precise about it.  If I were to be building such a cumulative case, I probably wouldn't have caught that, but now that you point it out, I'll be careful.  But I think you can still do it...let me unpack what I mean by that.

First, if one is being as precise as you are, I still argue it is "trivial", because in that case, Pr(theism | biology) >= Pr(theism) --- note here the greater than or equal to rather than the strict greater than --- if you include TAG in your background.  That is because TAG means Pr(theism) = 1.  So Pr(theism | biology) = 1.  So it is a trivial result as to whether you "add" the argument from biological design to your background knowledge.  In either case, Pr(theism) = 1.

So how in the world would you build a cumulative case with TAG included?  Well, since we're talking about epistemic probability here (which is a measure of belief rather than frequency), then you could say "Let 'A' be the event that someone believes TAG is true with a 60% probability".  Could you not then condition on "A"?  Would then TAG not be part of a cumulative case?  I think it could be.

In that case, TAG is just another part of your toolbox in the cumulative case for God.  This is where I fall because I think it's a powerful argument, but no one will be 100% convinced on the basis of this argument alone.  On a frequentist approach, either TAG is true, or not; just like either God actually does exist or not.  But in terms of epistemic/Bayesian thinking, the question is rather, how convinced are you that this argument goes through? If you are 90% certain of TAG, then both Pr(theism | A & B) >= Pr(theism | B) and Pr(theism | A) > 90%, where A = TAG is 90% probable and B = background knowledge.

If you argue for some reason it cannot be part of a cumulative case, then we are faced with two possible choices: either you accept TAG and then arguing further about the existence of God is trivial since you accept the proof from TAG, or you reject TAG and then we go on with the rest of the cumulative case.  Either way, any other evidence/argument I mount in favor of theism is at least neutral: in the former case it's irrelevant and in the latter it strengthens the case for God.

Which camp do you fall under?  Do you accept TAG and therefore need no further convincing on the strength of that argument alone?  Or do you reject TAG and therefore are open to discussing the strength of the other myriad arguments for God's existence?

Again, if you are like me, then TAG is a powerful argument and if correct then God's existence is 100% certain.  But we don't know for sure it's correct, meaning that, in terms of epistemic probabilities, God's existence is not 100% certain. Therefore, we marshall other arguments.

Regarding the Bayesian analysis of Dawkins's statements, it is specifically about the case for the fine tuning of the universe.  The general Bayesian analysis goes like this:

Pr(G | FT) = P(FT | G)*P(G)/P(FT)

where G = God exists and FT = the fine tuning of the universe is instantiated.  As usual, we can split the denominator into two terms:

P(FT) = P(FT | G)*P(G) + P(FT | ~G)*(1 - P(G))

Now, the fine tuning argument says that P(FT | ~G) = epsilon (ie, small).  Usually numbers like 10^-120 or 10^-10^123 are thrown around, but the exact number is not important, just that it's small.

For the sake of simplicity, let me just say that P(FT | G) = 1 (ie, God would indeed make a universe in which advanced life is possible, and of course by necessity such a universe would be finely tuned as we observe).  We can keep this term around for precision but I think it's easier to discuss over facebook if I make this assumption.  The results are essentially the same either way unless you want to argue P(FT | G) = epsilon also, which I think would be hard to justify.

Anyway, this leaves us with:

P(G | FT) = P(G) / (P(G) + epsilon*(1 - P(G))

So the only thing left here "unknown" is our prior probability of the existence of God.  Now, you can see right away that if the fine tuning argument is correct in that epsilon is small, then only if you have an absurdly low prior for God existing can you escape the conclusion that P(G | FT) is close to 1.  Well, that's exactly what Dawkins does.  He says, "It doesn't matter how improbable our universe is; the probability that God exists is smaller."  That's a sneaky statement, but what it means is that P(G) = 0.  The only number that could be a probability that is smaller than *any other number* that is also a probability is zero.  By definition.

Mathematically, Dawkins's statement is: for every epsilon > 0, 0 <= P(G) < epsilon.  This is *mathematically identical* to saying P(G) = 0.  But if someone's prior for God is zero, then there is no reason to have any discussion.  Dawkins is essentially saying, "I don't care what the scientific evidence for fine tuning says, I will choose to believe that God does not exist."  That is not reason or rationality, that is blind belief.  Belief, as it were, in spite of the evidence.  :-P

But let's instead say that your prior is also super-small.  Let's say it's much smaller than epsilon even.  Then you are left with:

P(G | FT) = P(G)/epsilon

In other words, the most hardened skeptic, unless he is exhibiting blind faith that God does not exist (and thus P(G) = 0 for him), would objectively increase his epistemic belief that God exists by orders of magnitude once the evidence for the fine tuning of the universe were examined.  And if you have a set prior for God's existence (and not a moving target so that as more evidence comes in, you "conveniently" make your P(G) smaller), all you have to do is wait a while.  As we discover more about the universe, I predict that epsilon will get smaller and smaller.  If I am right, then eventually, epsilon will either shrink past your set P(G), or you will have to find some other reason to reject this argument.  Or else you are fooling yourself.

Now, don't get me wrong, you can attack what I've said in a number of places.  I did gloss over what one might think P(FT | G) is.  Also, you can argue that the universe is not in fact finely-tuned.  However, in the first case, as I've said, unless you unjustifiably put P(FT | G) ~ epsilon or less, then it doesn't really matter what P(FT | G) is.  In the second case, you would be going against hard scientific data, and thus must object out of a precommitment to a non-theistic philosophy rather than objectively examining the evidence.  I think that in either case you are in a weaker position than the theist.

I can go through a similar Bayesian argument for the resurrection.  I like that one too.

Series: a discussion with Aron from Maryland

Dear all,
Last year, I began an internet discussion with a non-theist named Aron from Maryland.  At the moment, this discussion is ongoing, and will be continuously updated here, so check back often.

We started out talking about the Transcendental Argument for God's existence (TAG), and in the end agreed how it could be used in a bigger cumulative case.

We have since transitioned to discussing the fine-tuning argument (FTA).  It's great discussion, and I hope others will follow along.

Transcript of our discussion about TAG (we start transitioning to discussing FTA at the end):

A beginning to our discussion of the FTA, where Aron opens with acknowledging our general agreement of how to apply the TAG, and also suggests the probability that our universe would be the way it is (usually called "finely-tuned" in theistic circles) in not actually low:

I answer with some general questions for Aron to make sure we're not talking past each other:

Monday, July 7, 2014

Link: Richard Dawkins and Circular Reasoning

Over at The Cumulative Case, I've made a recent post about Richard Dawkins and his circular reasoning, which echoes a post from a while back here at the Two Books Approach.  In essence, I have attributed a statement to Dr. Dawkins that, if followed to its logical conclusion, means to deny that the fine-tuning of the universe implies the existence of God, is predicated on first assuming God cannot exist.  That is, the probability of God existing is identically zero.  Of course, this isn't logic or reasoning, it is simply blind faith.  Now, I don't suppose I'll know for sure if Dr. Dawkins really holds to this view, so for the benefit of the doubt, I will say that he does not.  Even so, I think it is interesting to unpack what the following statement means: "No matter how improbable this universe is by chance, the probability of God is even less."

An excerpt from the relevant post from The Cumulative Case:
If you start off assuming that God cannot exist, then no amount of evidence, no matter how strong, can budge you.  Dawkins is essentially saying, "I don't care what the scientific evidence for fine tuning says, I will choose to believe that God does not exist." That is not reason or rationality, that is blind belief. Belief, as it were, in spite of the evidence.
For the readers' convenience, I've pasted the relevant point from my old post (note the edit where I have made my statements more circumspect by inserting [many] where the word "all" used to be):
[T]he statement "no matter how improbable this universe is by chance, the probability of God is even less" is tantamount to saying "the probability of God existing is zero." Think about it. The only non-negative number that is guaranteed to be smaller than all positive numbers is zero. This is quite a strong statement. It goes far beyond saying God doesn't exist. It says that God cannot exist. In other words, Dawkins is using an assumption that God cannot exist to try to prove that God does not exist. It is a completely circular argument.
Here's another way to think about it, for the more math-oriented folks. In probability and statistics, the proof we're trying to make is something called a conditional probability. We see an improbable universe around us. What is the probability that God exists given we live in an improbable universe (ie, what's P(G|U))? Using Bayesian inference, we can easily come up with:
P(G|U) = P(G)/(epsilon + P(G)).
Here P(G) is the prior probability that God exists, and "epsilon" is the small chance that this universe came together by coincidence ([many] scientists would agree that epsilon is very small...something like 10^-50 or less). When doing Bayesian inference, you often have to bring in some a priori assumptions to assign prior probabilities (hence the name), so we have to guess at what P(G) is. But you never outright assume that P(G) is identically zero (or one). That would be the same as saying "no matter what our studies tell me, I will choose to believe X." (That's called blind faith.) Usually, when you don't know, you simply set your prior probabilities equal to 1/2. It's easy to see that P(G|U) (the probability that God exists given the universe we live in) would be extremely close to one for any reasonable choice of P(G). The only choice that makes P(G|U) small is P(G) = 0. Which is apparently what Dawkins wants to say.

Wednesday, January 22, 2014

Link: The Inevitable Consequence of An Atheistic Worldview

One of my favorite Christian authors is J. Warner Wallace (Cold Case Christianity), who gave a fantastic lecture here at NC State in December.  I was browsing his blog the other day and came across this piece where he describes an intriguing exchange between some skeptical readers of his blog.

In essence, one of the commenters came out and said in very plain words what the consequences are of an atheistic worldview.  The bottom line is there is no foundation for morality.  I recommend it as a quick read.

Thursday, January 9, 2014

Skeptics don't think Christians think

I have just now come to the realization that, even though there are fantastic arguments in favor of the Christian worldview and of the truth of the bible, many skeptics still think that Christian apologists are charlatans.  That is, these skeptics think that our reasons for belief are grasping at straws, and that our belief comes first, and this faith blinds us to the mistakes we are making in our arguments.  Or worse, that we know our arguments are bad, but we keep advancing them in hopes to keep the faith alive.

This really hit home with me when I considered several bad arguments against Christianity from the starting assumption that all arguments in favor of Christianity were wrong.  (That is, Christians have zero reason for their belief).  Check these out (and these are just a few):

"You just believe because your parents told you to -- therefore, God doesn't exist."  

This is a terrible argument!  But if you start with the assumption that Christianity has no arguments in its favor, then you see why this is compelling.

"You just believe because you were born in Western society.  If you were born anywhere else, you would have adopted the prevalent religion of that location.  Therefore, all religions are false."

This argument is so empty it's hilarious.  First, even if it were true, it doesn't invalidate Christianity.  And second, it's self-refuting: you could apply this argument to atheism (like I do here in "Objection 1").  So why is it so convincing to so many people?  It's because there is the underlying assumption that religions (especially Christianity) have no basis for their belief!  So you can't apply it to atheism, because that has a basis for its belief (so the assumption goes).

Religions are a mind-virus (a meme).  They spread because of societal and cultural pressures.  Therefore, God doesn't exist.

Again, this argument doesn't hold water unless you're already assuming there are no reasons for belief in God.  And again, this argument can be turned against atheism...but the person putting forth the argument doesn't realize that because they don't realize their implicit (and incorrect) assumption: that atheism has evidence for it but religion does not.

Wednesday, July 31, 2013

Even in the multiverse, our universe is rare

Last time I ended with the cliffhanger, saying the multiverse (the idea there are a vast number of other universes out there) strengthens the design argument for God.  This discussion stems from the widespread realization, from scientific data, that our universe appears "designed".  The constants of physics and structure of the universe are finely-tuned: they must be just-right in order for life to exist.  Even non-theistic scientists acknowledge this.  (See here for a great website that has compiled many quotes to this effect.)  However, what if there are an infinite number of universes, each with their own random laws of physics?  By sheer numbers then, we should expect at least one bio-friendly universe to exist.

And the fact that we exist says that such a universe exists.

This last point is incredibly important.  It is called a "selection effect".  Even though it's rare that a bio-friendly universe exists, the idea is that it is not rare for observers to note they live in a bio-friendly universe.  The very fact that observers exist (and are living) shows they must be in such a universe.

But here's where it gets weird.  It turns out that, of all possible universes with observers, our universe is still rare.  Because of the extreme degree of fine-tuning necessary to make this universe bio-friendly, it is actually far more probable that a universe composed simply of a star and a host of planets (including the life-friendly one) just popped into existence (POOF!) out of the quantum vacuum.  I repeat: it is far, far more probable that an entire life-friendly solar system just popped into existence with no explanation.

It gets weirder.  Considering those types of universes are more probable, and that presumably in some of those universes, life will have evolved to the point of being technologically advanced, it's actually more probable that we are just in a Matrix-like computer simulation from these advanced life-forms.  In that manner, we'd be "intelligently designed" (but also our world would not be "real").

It gets weirder.  Even more probable than the solar-system-out-of-nothing scenario, by far the most common type of universe with an observer(s) is one in which a single brain pops into existence, looks around and notes the nothingness in which it sits, and then pops out of existence.  (This is called the "Boltzmann Brain".)

All of these then beg the question: why do we live in a universe that is so extremely finely-tuned (to such a degree that it is prohibitively rare, even in a multiverse), when it's far more likely that we wouldn't live in such a universe?  The clear-cut answer is that our universe did not arise by chance.  We are not just a lucky accident of the quantum vacuum churning out random universes.  Our universe was supernaturally designed by the One who has the power and care to undertake such a creative event.

Thursday, July 25, 2013

The Multiverse: science or a cop-out?

Recently, over at, columnist Dennis Prager wrote a piece on "Why Some Scientists Embrace the 'Multiverse'".  The article is a good read; in the first part, Prager describes the incredible scientific evidence for the design of the universe for the benefit of life.  The bio-friendliness of the universe is undeniable, and is admitted by scientists of all stripes.  But the "design" of the universe then begs the question: who designed it?  Or, how did it come to be this way?

However, Prager then transitions into a discussion of the multiverse (the idea that there are many, perhaps infinite, universes out there).  If true, the multiverse could get around the problem of the fine-tuning.  After all, if there are an infinite number of universes out there, all with random laws of physics, there would just have to be one in which the laws were "just right" for life to exist.  No matter how improbable it would be for you to hit that bullseye perfectly, given an infinite number of tries, it's bound to happen.  And that's the universe we live in.

But Prager implies the multiverse is solely proposed by scientists in order to get around the fine-tuning.  This is incorrect.  The multiverse hypothesis is a direct inference from the laws of physics.  If we've got the equations of our own universe right, there is a very good chance there are other universes out there.  Just because it's impossible to detect them doesn't mean they aren't there.  And that certainly doesn't mean the multiverse hypothesis is some concoction by atheists to get around the fine-tuning.

So if the multiverse exists, and I don't think we can discount it, where does that leave the fine-tuning argument?  It does seem to provide a nice refutation of fine-tuning pointing to God as designer.  Perhaps that's why it's so popular, and why it gets so much attention.  (And perhaps that's Prager's actual point: that the multiverse is popular with scientists, even though there is no direct evidence for it, because it seems to satisfy their worldview.)  But the reality is, the multiverse only makes the design argument for God stronger.

Thursday, July 11, 2013

Is Dawkins spreading propaganda?

Well, despite the sensationalistic title of this post, I think the answer is probably "no, I wouldn't go that far as to say that."  But I have been amazed at some of the things he keeps on saying, held in tension with some things I know people talk to him about.  For example, he continues to deride all believers as people who do not think, yet he is acquainted with one of the greatest proponents for Christian thinking: fellow Oxford professor (and prolific author) John Lennox.

This all came together for me in an "aha!" moment when I read the first four sentences of this article about William Lane Craig (which by the way is a great article in and of itself and I recommend reading it; the first four sentences are almost irrelevant to the rest of the article) where the author depicts Dawkins as decrying the notion of giving a Christian apologist publicity.

This made me wonder: it is really about the search for truth and advancing science and reason for Dawkins?  Or is it about empty rhetoric, sound bytes, and attempting to control what people hear?  The irony of it all is that Dawkins (and now many others) blames the spread of religion on "memes".  Originally, memes didn't have to be funny images with catchy phrases; they can also be just what your parents taught you, or what your friends like, or what's cool at school.  Any cultural element that gets passed from one person to another could be a meme.  Yet, through the use of sound bytes, etc. (which appeal so much to this generation), it is actually atheism that is now propagating* by meme.  Very interesting.

* - By the way, the word "propaganda" has the same root as the word "propagate".  We now come full circle.

Saturday, July 6, 2013

Why am I both a scientist and a Christian?

In this day, it's en vogue to say that if you think rationally, then you give up Christianity.  No doubt this seems true.  In fact, many churches also promote this view (either implicitly or explicitly).  The internet is filled with anecdotes about teenagers who came with the hard questions, yet their pastors/elders/"heroes" in the church just told them to have more faith.

Talk about a recipe for unbelief.

The sad thing is that this is a complete misunderstanding, promoted by both Christians and non-Christians alike.  Last time I professed that I am both a scientist and a Christian, but I didn't say why.  Here it is: Science was birthed out of a Christian world.  It borrows Christian ideas about the world as basic philosophical foundations.  And most importantly (at least for me): scientific, philosophical, and historical evidence undergirds, rather than erodes, the reasonableness of belief in the God of the bible.

But don't take my word for it.  Here are a few sites that would agree (and these are far from exhaustive; they are just the ones that I thought of off the top of my head):

Sunday, June 23, 2013

I am a scientist and a Christian

There is a false dichotomy that most people believe in without even thinking about it: that either science is true, or religion (i.e. Christianity) is true, but not both.  For example, according to reviews of "The Unbelievers," that movie implicitly assumes this false dilemma and rides that assumption throughout.

But that doesn't hold water.  I am a scientist and a Christian, and far from internally being at odds with myself, the scientific (and engineering) knowledge I have strengthens my belief in God.

What's interesting is that oftentimes, atheists maintain their lack of belief in any god not for scientific or logical reasons, but for non-rational (emotional) reasons.  Take the oft-quoted Aldous Huxley on Christian morals: "We objected to the morality because it interfered with our sexual freedom."

Or infamous atheist Thomas Nagel: "I want atheism to be true and am made uneasy by the fact that some of the most intelligent and well-informed people I know are religious believers. It isn’t just that I don’t believe in God and, naturally hope that I’m right in my belief. It’s that I hope that there is no God! I don’t want there to be a God; I don’t want the universe to be like that."

(Incidentally, these quotes support what I was saying a few days ago in regard to Objection 4.)

For more, see this post on the Christian Apologetics Alliance webpage.

Thursday, June 20, 2013

A response to "Dear Believer, Why Do You Believe" part 2 of 2

Last time, I began a critique of the popular YouTube clip titled, "Dear Believer, Why Do You Believe".  The thing to keep in mind is that the main premise of this video is that no religious person has adequate reasons to believe.  If this premise were true, then the objections raised in this video actually hold some weight.  However, in that case, the objections would essentially be moot: if no religious person has good reasons for their belief, what is the point of raising more objections.

But instead, religious folk, and Christians in particular, have many reasons to believe!  If you follow my blog, you'll find some of those reasons.

As for the rest of my critique of the video, I have identified six common objections to religion in general, and Christianity in particular, and I offered a response to the first three last time.  Here I will go through the three remaining objections raised in this video.

The problem for the atheist who espouses the views in this video is there are not only many adequate reasons to believe in a god in general, and the Christian God in particular, but these reasons are also immensely compelling.  But even if they were only moderately compelling, the existence of such reasons would totally dismantle this video.  In a way, the narrator is underhandedly delivering a stinging insult to religious people worldwide, saying they live in the dark ages.

Objection 4: “Religions are just crutches to help us feel better.”

I wonder if religions aren’t just ancient constructs, in an attempt to explain unexplained phenomenon.  Though irrational in content, they are not irrational in their emergence.  But we no longer live in the dark; science is ablaze in our world, we no longer live in the cave!  We no longer require comforting stories that make us feel safe, comforted or valued.  Isn’t it time our faith matches our discoveries?  Our ideas our new perspective?  Greater awe in reality rather than in fantasy?
This has many problems, first and foremost that atheists may hold their lack of belief in any gods also as a crutch.  If there is no cosmic being, then who am I held accountable to for my immoral actions?  No one.  OK, not every atheist feels this way, but certainly some do.  In the same vein, not every Christian feels like God is a crutch.  Sometimes, I wish God's influence on my life would just go away so I could be autonomous.  I mean, who doesn't like the idea of being their own master?  Who wants to submit to someone in higher authority than themselves?

On the other hand, again, if there are reasons to believe in God, then crutch or not, it is something to consider.

Objection 5: “It's arrogant to think you have the right religion”

Isn’t it time to stop thinking that we are somehow the reason why this universe was made?  That our culture is somehow better than other cultures?  It’s time to learn how the universe really is, even if that deflates our conceits, and forces us to admit we do not have all the answers.  You must confront these fundamental questions.  
I wonder why this is arrogant?  I've posted on this before, but it bears repeating: ideas aren't arrogant.  If you follow the evidence where it leads, how is that arrogant?  Furthermore, taking the position that the narrator does, how is his position not arrogant? Saying believers live in the dark ages?  The narrator surely thinks he's in a position of privileged knowledge.

Objection 6: “It's arrogant to think we occupy a privileged place in the universe.”

Isn’t it time to stop thinking that we are somehow the reason why this universe was made? That our culture is somehow better than other cultures? It’s time to learn how the universe really is, even if that deflates our conceits, and forces us to admit we do not have all the answers.

Last point, but it's beginning to sound repetitive: this would be valid if there were no evidence that we do indeed occupy a privileged place in the universe (in terms of importance).  But there is evidence.  Perhaps there is still debate going on about that, but the scientific data are fairly clear: there are only a handful of places and times in the universe that intelligent life could exist (and maybe only one unique time and place).  If that is what the data say, then again: how is this arrogant?


Every point made in this video seems nice on the surface, especially if you are already indoctrinated to the ways of the new atheists.  Especially if you accept without question the assumption that science and reason are on one side, and faith (which is blind) on the other.  But just for a moment examine your assumption.  If there are good reasons to believe in Jesus as Lord, then nothing this video says makes any sense.  There are no salient points made.

Wednesday, November 28, 2012

A response to "Dear Believer, Why Do You Believe" part 1 of 2

The popular YouTube clip titled, "Dear Believer, Why Do You Believe" is an attempt to show the fallacy of religion and religious belief. The video is very well done, and has a narrator with a soothing voice calmly raising several objections to religion.  There seems to be real power in this video because the objections keep coming, keep piling up, and if the unwitting believer (or unbeliever) watches, it's really easy to be either bewildered by the objections, if the believer is not ready to answer them, or to say, "Yeah, that's so true!" if you are an unbeliever.

The problem is, this clip is filled with logical fallacies and arguments that are easily shown to be false.  In this blog post, I will go through the main objections to religion raised in this video (which also happen to be commonly used by unbelievers) and show how each one of them fails.

Summary of the video

Much of the video is devoted to the question of why a religious person believes.  The implication is that believers have no good reason to believe.  In fact, you only believe because your parents told you so.  The narrator asks, since there are many religions out there, which cannot all be right, then how would a person choose one religion over any other?  The narrator then claims that this means no religions are indeed correct.

The end of the video pays homage to modern science, saying that "now we know better".  The narrator does not blame ancient peoples for turning to fantasy to comfort themselves, but in this day and age, because of the advent of modern science, we should leave those superstitions behind.  The implication is that, any reasonable and clear thinking person will cut him- or herself free from the fairy-tale of religion and realize the "truth": there is no god.

The irony is that, if you are using reason to help form your basis of belief regarding the big questions, such as, "Who am I?", "Why are we here?", and "Is there a God?", you will soon see that this video has nothing logical to say about it.  In fact, most of the objections against religion raised by this video are self-refuting, a hallmark of poor reasoning.

In this series of this posts, I will go through six objections to religion in general (and Christianity in particular) portrayed by this video.  In each case, I will state the objection as I see it being raised by the video (either implicitly or explicitly), paraphrase (not direct quoting, although I will put it in quote blocks) the relevant parts of the video, and then respond to the objection(s).

Objection 1: “You’re only a Christian because you were born in America to Christian parents.”

Is the faith you practice the dominant one within your culture?  Aren't you suspicious that most people adopt the religion of the society in which they were born? Yet remain convinced they've found the one true faith?  Did you know that most people choose it not for reasons, but because they were born into it?  Can it be just an accident of geography?  Did you know nearly all religious devotees believe what they are taught to believe by their parents?
This is the main thrust of the video: religious people around the world have no reason to believe what they believe.  I actually have no idea whether or not the assertions made by the narrator here are true.  Is it really true that most people don't choose their religion for good reasons, but because their parents told them to?  Maybe so.  But this objection to religion commits two fallacies: (1) it is self-refuting (this is the death knell of any argument), and (2) it commits the genetic fallacy.

It is self-refuting because it cannot withstand its own scrutiny.  The implication is that since religious people only believe because they were born in a culture dominated by their chosen religion, then that religion cannot be true.  But the same can be true of unbelievers of any stripe.  You are only a postmodernist because you were born in late 20th-century/early 21st century America.  Or you are only an unbeliever because you were told so by your parents. Yes, I understand that many unbelievers in America (especially young people) grew up in the church, but since there is a trend of young people leaving the faith, I could just as easily say it's a cultural thing for young people to do (and not based on reasons).  Especially if these young people leaving the faith are spouting the same self-refuting objections found in this video.

This objection also commits the genetic fallacy, which says that because a belief's origin is suspect, the belief cannot be true.  But this is incorrect: just because someone's belief in God stems from their upbringing does not necessarily mean the belief is false.  It could be false, but you would have to bring a valid argument against it to show that, not a fallacious one such as this.

Objection 2: “How do you know you have it right?  Have you checked out all the other religions of the world? And if every member of faith feels just as strongly as you do, what are the odds you’re right?”

There are 2 dozen major religions.  Furthermore, did you know there are more than 45,000 denominations of Christianity alone, each claiming to understand ultimate truth better than the rest?  Each member of every faith is just as devoted and sincere and convicted as you? Did you know they also read infallible texts, have airtight apologetics, have experienced miracles, etc.?  Yet, since every religion is mutually exclusive, they cannot all be right, right?  If every member of every faith feels just as you do, what are the odds you’re right?  
In this little tight block of paraphrased-text from the video, the main common objection is that there are also other believers out there; how do you know they're not right, and you're not wrong?  The problem with this objection is clear: just because there are others out there who don't believe as I do, does not mean that what I believe is wrong.  The veracity of a religion, or of any other point of view, is not a popularity contest, in which a position must certainly be false if there are enough people who hold a different position.  This objection has three major problems with it: (1) it is self-refuting, (2) it is internally inconsistent, and (3) assumes the correct point of view is simply a popularity contest.

Before I go into those problems, I would like to commend the narrator for holding a position that is often unpopular among unbelievers, at least among the post-modernist types: that every (or nearly so) religion is mutually exclusive.  No, it is clear that not all roads lead to God.  After all, most of the time, the basic claims of a religion are in direct opposition to the basic claims of other religions.  For more, see this post by Eric Chabot in response to "Dear Believer..."

This objection is self-refuting again because it cannot stand up to its own scrutiny.  Atheism is also a set of beliefs that not everyone holds.  There are many out there whose religious beliefs are just as sincere and convicted as the beliefs held by the atheist. And certainly atheism contradicts most if not all religions.  They can't both (atheism and a given religion) be right, right?  So by this argument, atheism is itself subject to this popularity contest, and if that is the case, hands-down it will lose.  No, in order to advance atheism as a "better" choice than a given religion, you actually have to marshal evidence for it, not just say that there are too many religions out there to pick one for certain.

It is also internally inconsistent.  If we are to take the narrator at his word (and I think this is highly suspect), we note that he makes claims such as, "they all have infallible texts, air-tight apologetics, and have experienced miracles".  First, it is certainly untrue that multiple conflicting religions have air-tight apologetics.  Only one at best can have "air-tight" apologetics.  Furthermore, regarding the infallible texts and miracles, if that is true, that argues far more in favor of at least one religion being correct, or at least that the atheistic worldview is incorrect.  After all, on atheism, there are no infallible texts nor miracles experienced.  What the narrator is doing here is, in a backhanded way, saying that all religions claim to have these things, but they really do not.  If that is true, then yes, let's abandon religion.  But this is a bald assertion that needs to be supported by well-reasoned arguments. No such arguments are put forth here.  Instead, I would argue that Christianity in particular does have air-tight apologetics, making it the clear choice over all other religions, including atheism.  And if Christianity does indeed have air-tight apologetics, where does that leave this argument?  It leaves it lacking any apologetic reasoning of its own.

Finally, it is clear that the correct point of view is not the winner of a popularity contest.  Like I mentioned above, if that were true, then Christianity would be the winner.  On this view, the atheist should "reasonably" abandon his faith in atheism and turn towards the God of the bible.  In fact, this objection is at direct odds with his first objection in the video.  If "truth" is voted in, then Christianity would always be the winner, since people (according to the narrator) choose their faith based on what their parents (or some other meme) told them.  How then would a majority-dominant religion (and thereby the "correct" religion by the narrator's point of view implicit in this objection) ever be overturned?  It's correct because it's popular, and then it's passed on to the next generation as the majority religion by meme.  The final irony with this is that the narrator clearly does not believe that the best belief set is chosen by popularity.  If you watch the whole video, he espouses using reason, testing, and logical thinking to test which worldview is correct.  So, in the end, he answers his own question: "How do you know you have it right?"  The answer is: because of logic, reason, and testing the spirits.

Objection 3: “You're an atheist too, just for one less god than I am.”

I've been told my unbelief is guarantee of missing heaven and going to hell, but whose heaven/hell? Should I, just to be safe, accept God? But whose God?  Given so many options, what are the chances?  Might I be better off wagering on no God rather than the wrong God? What if you’re wrong?  What if not Jehovah, but Allah?  Or Wu-tan?  Or some other god on the other side of the planet you've never even heard of? 
Truth is, you already know what it’s like to be an atheist for all gods but your own.  The way you view them (other people) is the same way they view you.  Every devout Hindu, for example, has embraced his faith for the exact same reasons you've embraced yours. Yet you do not find his reasons compelling, nor do you lose sleep at night wondering whether you’ll wake up in his hell.  Given this, is it so hard to see why some of us just take our atheism one God further?
I am often amazed at this line of reasoning, which I have heard several times before.  It seems so inane to me, I am surprised that people still use it.  It's so baseless, yet frequent, that I often wonder whether there is some subtle point here that I am missing.  If so, I would like to have someone explain it to me more fully.  For now, I will simply critique it as it appears in the video.  This objection fails because the definition of atheism is belief in no god, not belief in one to the exclusion of other (possible) gods.  It also fails because there are actually very good reasons to believe in at least some general deity, which of course rules out atheism.

So, how could one who believes in at least one god (a "religious" person) at the same time not believe in any god (an atheist)?  The entire premise of this objection is absurd in the strictest sense of the word.  It is, by definition, contradictory.  However, I think it might be best to give the benefit of the doubt and simply assume the narrator was using a turn-of-phrase to really call into question how a believer knows that he has the "right" god.

In that case, the narrator is trying to argue that all religions have the same evidential basis: zero.  If that is the case, then he is right starting from Objection 1: we have no reason for choosing our own set of beliefs except that they have been thrust on us.  So then, how can we possibly look down on others in the world that also believe for no reason?

However, this objection falls flat on its face because it only holds water if there are no good reasons for belief in a particular god.  But it actually gets worse for the atheist: not only are there good reasons to believe in the God of the bible in particular, but there are also good reasons to believe in at least some personal, transcendent, omnipotent, omnibenevolent, omniscient god in general, including the cosmological, moral, teleological and arguments, as well as the argument from reason.  These would clearly rule out atheism as a foundation for belief, but not the major monotheistic religions of the world.

Tuesday, September 4, 2012

Do extraordinary claims require extraordinary evidence? (Part 2)


Last time I introduced the topic, claiming that miracles do not need miracle-level evidence to support them.  The reason: you cannot assume your conclusion before the argument begins!  That is the mistake that atheists make (perhaps not realizing it) when they state that extraordinary claims require extraordinary evidence.  But like I said last time, you cannot a priori assume that miracles cannot happen; if you do this, there is no reason to have the discussion. 

Below, I show this rather rigorously using Bayes' Theorem, in a combination with a very simple analysis of the prior probability of a miracle happening.  I also put forth the Resurrection as a concrete example.  Some skeptical readers may be disgruntled with some of the numbers I put to things.  But even so, keep in mind that I'm not after some mathematical proof  beyond a shadow of a doubt that a given miracle did occur. No, I am simply showing that the statement "extraordinary claims require extraordinary evidence" is false.  Indeed, you'll find that, even with very conservative assumptions, miracles can be plausibly supported by ordinary evidence.

But readers be forewarned: there is a lot of math below!

The mathematics of Bayes' Theorem

To put things mathematically, Bayes theorem tells you how to evaluate P(A | B): the probability of a proposition, "A", given (i.e., in light of) another proposition, "B".  To see this, note that the definition of such a conditional probability is:

P(A | B) = P(A & B)/P(B).

If we multiply through by "P(B)" then we get:

P(A | B)*P(B) = P(A & B).

Since "A" and "B" are interchangeable in the right hand side of this equation, you can also write:

P(A | B)*P(B) = P(A & B) = P(B | A)*P(A).

Moving P(B) back to the other side:

P(A | B) = P(B | A)*P(A)/P(B).

Let's put some concreteness to this.  Say "A" is the proposition that some miracle happened (for simplicity, call it "M" instead of "A").  Now say "B" is the quite ordinary evidence for said miracle (and call it "E" for evidence).  Now:

P(M | E) = P(E | M)*P(M)/P(E).

In other words, the probability that a miracle happened, given you have evidence for that miracle, is how well the miracle can explain the evidence, weighted by how likely you think the miracle and evidence should occur on their own.  These are called prior probabilities. That is, P(M) is, "What do you think is the probability of a miracle happening before you consider the evidence?"  And P(E) is, "What do you think the probability of the evidence happening is, without considering a miracle happened?"  Since the evidence is "ordinary", P(E) is probably not too small.

But it seems we're stuck with this nasty prior probability, P(M).  Surely the probability of a miracle happening is so small (by definition) that you must then conclude that P(M | E) is never going to be large enough to convince someone, right?  That is, unless P(E) is super-duper small.  Unless the evidence is also extraordinary.  Hence, the conclusion that to prove a miracle you need miraculous evidence.

This is where you have to question your presuppositions. This is where you have to take a second look at what goes into the prior, P(M).

Why you don't need miraculous evidence to prove a miracle.

The probability of any proposition, A, can be split up into two parts contingent on another proposition, B:

P(A) = P(A | B)*P(B) + P(A | ~B)*P(~B),

(where "|" means "given," and "~" is a negation).  In our case, what's P(M), the prior probability of a miracle, M?  It can be split up into two parts; the probability of a miracle happening given that God exists (G) and the probability of a miracle happening given God does not exist (~G):

P(M) = P(M | G)*P(G) + P(M | ~G)*P(~G).

This is mathematically true, and also philosophically sound, because if you are arguing about whether or not miracles are possible (and usually it's an argument between a theist and an atheist), you cannot a priori assume that God does not exist.  That is the basis of the whole argument.  If someone assumes the other person's position is impossible (probability zero), then there can be no discussion.  So you cannot assume P(G) = 0.  You can assume it is small, but not arbitrarily small (as Dawkins attempts to do).

So let's look at the terms that make up P(M).  I argue (and so would the atheist) that P(M | ~G) is essentially zero.  A miracle is not going to happen if God does not exist, because by definition it is an extraordinarily rare or impossible event.  So the second term disappears, and we're left with:

P(M) = P(M | G)*P(G).

I think we can successfully argue that P(M | G) (ie, the probability that the miracle in question would happen assuming God exists) is not vanishingly small. (If we are specifically saying G = God of the Bible, and M = the Resurrection, then I would say P(M | G) = 1.)  So the only way you end up with a zero prior for a miracle happening is if you assume that God cannot exist (ie, P(G) = 0).

Note that this is different from believing God does not exist.  Atheists believe God does not exist, but no self-respecting atheist believes God cannot exist.  If you ask someone whether they think P(G) = 0 and they say yes, the conversation is over.  That person believes that God cannot exist and therefore nothing you say can convince them.  You always must leave room for your beliefs to be falsified.

So P(G) > 0.  If you are talking about any God, then P(G) should be higher than 1/2, since more than half of all people believe in a god of one form or another (and if we're just basing our priors off of low-shelf statistics, which is what you normally do).  Along those lines, if you're talking about the God of the Bible, then P(G) is more like 1/3.  But even if you are speaking to a hardened atheist, such as Richard Dawkins, then P(G) is as high as 1 - 6.9/7 = 0.0143.  I would be willing to make that allowance.

You can evaluate P(M | G) in various ways.  If the god you are talking about has a holy text that claims the particular miracle in question (as in, the Bible and the Resurrection), then I would say P(M | G) = 1 (for all intents and purposes). On the other hand, if you are just attributing some random "miracle" to some random god, then it gets tricky.  For the sake of argument, let's say P(M | G) is a conservative one out of ten.  This means P(M) is rather high: one out of a thousand!  We take insurance policies out against probabilities more remote than that.  We play the lottery on the hope of winning big with probabilities far more remote than that.

If you are still disgruntled at my analysis of P(M), keep in mind that my argument for P(G) is essentially unassailable.  If you deny that argument, you are entering into the land of logical fallacy.  You may question my choice for P(M | G), however.  In that case, let's just leave P(M) equal to "some small number" p.  That way, we can see later what Bayes' Theorem does, and try to agree on a value for "p" later.  (Just remember: you can't make p = 0 a priori.)

Finishing the analysis

Now that we are armed with the knowledge that p can't be equal to zero, let's go ahead and complete our analysis using Bayes' Theorem.  We last left Bayes Theorem as:

P(M | E) = P(E | M)*p/P(E).

We can split P(E) up in the same way that we split up P(M), but this time we will condition it on "M":

P(E) = P(E | M)*P(M) + P(E | ~M)*P(~M),


P(E) = P(E | M)*p + P(E | ~M)*(1 - p).

Putting this back into the equation for P(M | E):

P(M | E) = P(E | M)*p / (P(E | M)*p + P(E | ~M)*(1 - p)).

If we rearrange the P(E | M) factors:

P(M | E) = p / (p + (1-p)*P(E | ~M)/P(E | M)).

Now we see there are two operative variables here: "p" (the prior probability of a miracle; remember, this cannot equal zero), and the following ratio:

R = P(E | ~M)/P(E | M).

This last term is the explanatory power of the miracle.  How much more likely is it that the evidence would have happened if miracle did not occur over if the miracle had occurred?  If the miracle happening makes the evidence more likely to occur, then R < 1.  If the miracle happening makes the evidence less likely to occur, then R > 1.  Obviously, if you are marshalling evidence for a miracle, let's hope you've chosen something that favors the miracle happening, so then R < 1.  How much less than one, of course, depends on the particular miracle you are investigating and what evidence you have for it.

At any rate, this gives us a very simply formula for the probability of a miracle happening given the evidence at hand:

P(M | E) = p / (p + (1-p)*R).

To make things concrete, let's choose a specific example.

A concrete example: the Resurrection 

Let's now suppose the miracle, M, we're investigating is the Resurrection.  Of course Habermas and Licona have presented five "minimal facts" that most biblical scholars, skeptical and conservative, agree upon in regards to the events surrounding Jesus' death.  However, since this is an internet blog and not a scholarly work, and since that means there are many hyper-skeptics out there who might visit and comment on this blog, let's just stick to one piece of evidence: the conversion and martyrdom of the early church fathers.  And, let's just stick with two church fathers: Paul and James.

In this case, the probability P(M | E), what we wish to find, is the probability that the Resurrection occurred, given the (ordinary historical) evidence that Paul and James were both converted from hostility/skepticism and were both martyred for their beliefs (never renouncing the claim that they saw the risen Lord).

The probability p = P(M) = P(M | G)*P(G), where P(G) is the probability that the God of the Bible exists, and P(M | G) = 1.  So your prior p is essentially how likely you think it is that the God of the Bible exists.  Remember: the world's most famous atheist says this is about 0.01 (more or less. I admit that if he were interviewed, he might say the particular God of the Bible is even less likely to exist than any random god, but then why does he spend so much time focused on Christianity?).

So the question boils down to: what's R?  In words, R is the probability that Paul and James would die for their beliefs given the Resurrection did not happen, divided by the probability that the they would die for their beliefs given the Resurrection did happen.  It seems extremely, extremely, extremely unlikely to me that, if the Resurrection did not happen, then both Paul and James would be converted and go to their deaths proclaiming Christ is King.  But if it is even just 10 times more likely for the Resurrection to make more sense about either man dying for Jesus, then R = 0.01, and we get:

P(M | G) = 0.01 / (0.01 + 0.99*0.01) > 0.5

Now, you may not agree with me that Paul and James actually did convert and actually did die for their beliefs.  You may not even agree with me that the Resurrection makes more sense of them dying for their beliefs over the Resurrection not happening.  But what you are now forced to accept is that it does not take much in the way of "extraordinary" evidence for even a miracle to be plausible.  Remember, I took the position of the most die-hard atheist and a pitiful collection of historical evidence (compared to the wealth of historical evidence that we do have), and a conservative estimate of what that might mean, and I still am forced to arrive at the conclusion that the resurrection is more than 50% likely.


In these posts (including last time), I have shown, using careful (and conservative) mathematical and philosophical arguments that it does not take extraordinary evidence to back and extraordinary claim.  This is based on the recognition that you cannot assume your conclusion before you start. (That is the only way that you could ever arrive at the conclusion that extraordinary claims require extraordinary evidence.)  Once you give even a little ground to the possibility that God exists, and you must do so for intellectual honesty, you are forced to accept the fact that, given enough ordinary evidence, such as well-attested to historical facts, or personal testimony, that miracles actually can be plausible.  And while it is true that the evaluation of some of these probabilities are subjective, keep in mind this was not meant as a mathematical proof of any particular miracle, only a demonstration that, even with very conservative assumptions, miracles can be plausibly supported by ordinary evidence.

Sunday, August 26, 2012

Do extraordinary claims require extraordinary evidence? (Part 1)


How many of you have heard the statement, "Extraordinary claims require extraordinary evidence?" This is a common soundbyte from skeptics to try to discredit the existence of miracles.  But more often than not, it's used incorrectly, and that sort of disappoints me, because it shows that folks are not thinking logically.  Those who hold to this claim are essentially saying that they require evidence that is as miraculous as the miracle itself for them to be convinced a miracle happened.  Do you want to convince someone of the Resurrection?  It would take something on the order of lightning in the sky that spelled out, "Jesus rose from the dead," to convince such a skeptic.

It is actually rather simple to show this argument against miracles is false: it's because the argument only holds when you first assume miracles cannot happen.  And if you assume miracles cannot happen, then of course you are going to conclude that no evidence is enough to prove a miracle.  This is the mistake Hume made, the mistake the Jesus Seminar folks made, and the mistake that Bart Ehrman makes.

But you cannot a priori assume that miracles cannot happen; if you do this, there is no reason to have the discussion.  It is a form of circular reasoning.  Therefore, you must instead make an allowance (however small) that they can happen.  If they can happen, then any sort of everyday evidence could be evidence in favor of a miracle.  The question would then become whether the evidence is sufficiently in favor of a miracle to make someone believe, not whether something as commonplace as eyewitness testimony could be evidence of a miracle.

This can be shown rather rigorously using Bayes' Theorem, which I will do next time.  (Be forewarned: it can be a bit technical, but if you like math, or even if you don't, but you don't mind getting out a pencil and paper and following along, it should be pretty straightforward.)  Below I just give a brief, intuitive introduction to Bayes Theorem.

The intuition of Bayes Theorem

First of all, I love Bayes Theorem.  I've talked about it several times on this blog, mostly because it's really good to show that indeed, miracles can happen.  It's also super-easy to use; you just have to know a few things about probability, which are all taught in high school (I think).

Bayes Theorem is what helps us answer questions about what might be true (i.e., the converse of what we know to be true). Here's what I mean.  Let's say we know that for sure, the statement "if A then B" is true.  This means that if we know that A is true, then B must be true. But this does not mean that if B is true, then A must be true. But it seems like "B" being true adds some weight to "A" being true.  Bayes Theorem is how we figure out just how much weight that is.

Here's an example in which "B" being true definitely does not imply that "A" is true.  Let's say the statement "If I am swimming a race against Ryan Lochte (A), I will lose the race (B)" is true. Then let's say I swim in some race, and later tell my friend that I lost (B).  Can my friend infer that I must have been swimming against Ryan Lochte (A)?  Of course not.  There are many other swimmers out there that I would lose to.  In this case, B does not even come close to implying A.

On the other hand, here's an example where it seems B almost implies A: If you stand out in the rain (A), you will get wet (B).  Here, A implies B.  Does that mean if someone is wet, they stood outside in the rain?  No, but what happens if you add further evidence to the scenario?  You are in a shop, and someone comes in from the outside and they are dripping wet.  You'd probably conclude that it is indeed raining outside.  Adding further evidence, what if everyone who came in either had a wet umbrella, a wet raincoat, or was just wet (on their clothes)?  Now add the fact that when you went into the shop, you noticed dark clouds in the sky.  So yeah, you don't need to actually see the rain to be pretty sure it's raining.  (Thanks to for inspiring this example.)

That's a brief, intuitive example of how Bayes' theorem works.  The more evidence that's in favor of an event (A) above and beyond other explanations, the more you can be certain that, given said evidence (B), A is true.

Monday, June 18, 2012

Exclusivity and Arrogance

In our postmodernist/relativist/pluralistic culture, much has been made about the exclusive truth claims of Christianity.  A common complaint about this claim is that Christians are arrogant to say that only they know the truth, and that only through their God can people go to heaven.  With this complaint, the implication is that Christianity is therefore untrue.

This criticism of Christianity's exclusivism is totally understandable, as exclusive claims do not sit well in our culture.  But at its core, this criticism completely lacks logical/reason-based support.

A summary of my points

Here are three reasons why this argument has no ground to stand on (note: the first two were inspired by a recent WLC podcast that I listened to, although I had heard these arguments before.  I claim the final argument as my own musings):
  1. It is a classic example of the logical fallacy called an "ad hominem" attack: whether or not someone is arrogant has nothing to do with whether their claims are true.
  2. It is a double-edged sword: people criticizing the claims of Christianity based on their exclusivity are often religious pluralists, and pluralism is itself an exclusive truth-claim.
  3. It is actually arrogant to deny God: when there is ample evidence that a creator-God made the universe and humanity itself, to claim that we have figured out there is no God (or that we don't need our creator-God) is quite an arrogant claim.
For the interested reader, below I go into more detail about each of these three points.

It is an ad hominem attack

The heart of this argument is that someone who is claiming Jesus is the only way is arrogant, and therefore, you can discount their claim.  However, put this way, this argument clearly holds no water.  Just because someone is arrogant is absolutely no reason to consider their claim to be false. I could be the most arrogant person in the world, but I could also be completely right about things.  There are probably plenty of really arrogant professors out there who know their own field of research really, really well.  The fact that they are arrogant does nothing to discredit the truth of what they say.

Another way to expose faulty thinking is to put the argument into a syllogistic form.  In such a form, fallacies become obvious.  Here is the implied syllogism:

(1) All claims made by arrogant people are false.
(2) Because Christians say Jesus is the only way, they are arrogant.
(3) Therefore: Their claim that Jesus is the only way is false.

The logic is correct, but clearly both premises (1) and (2) are false, making the conclusion completely unverified by this argument.

Rebuttal: "But the complaint is not that the person who makes the truth claim is arrogant, but that the truth claim itself is arrogant!"

Response: How could a claim, which is a proposition that can be either true or false, be arrogant?  This is a category error.  People are arrogant.  Truth claims are either true or false.  However, it is an exclusive truth claim, but this has nothing to do with whether that truth claim is true or false.  Its exclusivity may be unpalatable to our pluralistic culture, but that does not prove it to be false.

It is a double-edged sword

In my informal study of philosophical arguments for and against God, I've found that many times, false arguments are self-defeating.  That is also true of this particular criticism of Christianity's exclusivism.  To understand this, you have to realize that religious pluralism, the worldview from which this criticism originates, is itself an exclusive truth claim, and therefore, by this argument's own standards, originates from an arrogant person.

The religious pluralist, as I understand it, says that all religions are equally true (or equally false).  However, it cannot be the case that all religions are equally true, as the foundational beliefs of most religions are mutually exclusive.  Therefore, to claim that all religions are equally true is either demonstrably false, or it is watering down the world's religions beyond recognition.  In either case, you are taking a position that is either clearly false, or one that is making a claim that only the religious pluralist really knows what all the world religions are all about: that they are all the same.

On the other hand, claiming  that all religions are false is equally exclusive.  The biblical stance is that only Christianity is fully true.  Based on that, the Christian would take the point of view that all opposing religions, worldviews, and philosophies are false.  The pluralist is saying that only hard pluralism (that all religions are false) is true: but clearly this is an exclusive truth claim!  Therefore, the argument against Christianity's exclusivism is a double-edged sword, which can equally be applied to the critic of Christianity.

It is actually arrogant to deny God

If you have read this blog enough, you have probably encountered my writings that describe the scientific reasons for a belief in God.  In fact, I think the scientific data are so compelling that they really force the God of the bible as their only logical explanation.  In that case, then to deny the sovereignty of God is to basically put yourself as god of your own life: quite an arrogant maneuver if indeed you owe your existence to your Maker.  It reminds me of Isaiah 29:16, which says,
Shall what is formed say to the one who formed it, “You did not make me”?  Can the pot say to the potter, “You know nothing”?
Look at it this way.  It would be quite self-centered for a teenage boy to say to his parents, "You never did anything for me!"  This is to his parents who brought him into the world, cared for him when he was completely dependent on them, gave him a place to live, clothed him, fed him, brought him up with love and discipline, etc.  For him to deny that would be ludicrous.

In the same way, there is ample scientific evidence that shows God created this universe specifically for us to live here on earth at this time.  The fine-tuning necessary for something resembling human life anywhere at any time in the universe's history is staggering.  This care and "effort" that God has invested in our lives through creation, not to mention through the incarnation and atonement, goes far beyond what any set of parents do for their children.

Now, you may or may not agree with me that there is ample evidence to believe in a God.  If not, then convincing you of that would be the subject for another time.  But at least understand this: if there is ample evidence that the God of the bible exists (and thus the universe was created by Him), then to specifically deny this evidence so you can deny his existence so you can be lord of your own life could be taken as highly arrogant.  This means that the argument against Christianity's exclusive truth claim can only be validated when first the critic examines and plausibly/reasonably rejects the implications of the scientific evidence for God.  And even then, the other two (above) defeaters of the argument still hold.

One more set of thoughts I'd like to leave you with.  You should keep in mind that most people do not specifically deny God for this reason (so they can be lord of their own lives), or at least, most do not admit as such.  But I think in light of this evidence that God exists, each person at least owes it to him or herself to examine that evidence very carefully, and with cautiously-guarded reasoning.

Monday, June 4, 2012

Returning from vacation

After a couple weeks of vacation, I feel a bit rested now, and with the summer being here, and my teaching load gone, I hope to write a bit more.

I was just musing the other day about the way my post topic have been trending for the past year or so, and I realized that I have gone very far away from what used to be my passion: science apologetics (or evidential apologetics).  Instead, philosophical and "presuppositional"-type arguments have caught my fancy of late, which is sort of a dangerous thing since I am definitely not an expert in these things.  But take, for example, something that's been on my mind lately, which is the common atheist soundbyte: "extraordinary claims require extraordinary evidence."  Definitely a pet peeve of mine, and something that I will be blogging about in the near future.

Saturday, May 12, 2012

A funny blog post on How to Refute Christianity

I was browsing through JW Wartick's blog page (Always Have a Reason), and found this on one of his really recommended posts:

How to Refute Christianity: A Handy Guide

Quite humorous, and although not exactly scientifically or logically sound, it's not meant to be. It's just supposed to be funny.  I recommend reading.