WL Craig: The Kalam Cosmological Argument

Craig's arguments for God, Pt 2

Abrahamic religion, you know, the one with the cross...

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Re: WL Craig: The Kalam Cosmological Argument

#2221  Postby Thommo » Jan 06, 2015 3:49 pm

Thommo wrote:Sorry, the conclusion doesn't follow there either.

The argument doesn't show anything about the relative probability of a God-designed universe compared to a not God-designed universe. At best all it shows is that the unknown probability of God's existence given the universe appears to sustain natural laws is lower than some other unknown probability of God's existence given an agnostic status about whether the universe appears to sustain natural laws.


Re: this, if anyone is unclear, let's give an argument of the same form as those above, but for a more mundane phenomenon.

On my table is a coin. A standard UK £1coin, which has a "heads" and a "tails". It's probably not exactly evenly weighted, but a few tosses with it show that it seems to come up heads and tails with at least approaching equal frequency.

(i) What is the probability that I deliberately placed the coin on the desk, rather than tossed it and let it fall?
(ii) What is the probability that I tossed the coin and let it fall on the desk, rather than placed it there?


I now tell you that the coin is heads facing upwards:

(iii) Is the probability that the coin was placed heads up now higher? Is it higher than the probability the coin was tossed?
(iv) Is the probability that the coin was tossed randomly now higher? Is it higher than the probability the coin was placed?


Bear in mind I am only here and able to truthfully tell you that the coin is facing heads upwards because it is facing upwards, just as in the original scenario.

The answer is of course the same to all questions: we don't know the probability.
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Re: WL Craig: The Kalam Cosmological Argument

#2222  Postby Rumraket » Jan 06, 2015 4:13 pm

Thommo wrote:Sorry, the conclusion doesn't follow there either.

The argument doesn't show anything about the relative probability of a God-designed universe compared to a not God-designed universe.

It doesn't purport to show that.

It tells us whether the particular evidence we have, ("fine tuned constants that allow life") is more probable on a designed vs non-designed universe.

Given that all non-designed universes with life would necessarily have such constants that allow for life, the probability that we should observe such a set of constants in a universe with life if it was not designed, is 100%.

This is NOT the case on the designed by a god hypothesis. Here such a condition is only a subset of the full set of possibilities, so it CANNOT be 100%.

Therefore all else being equal and given that we observe "fine tuned constants that allow for life", this evidence is more probable on the not-designed than it is on designed-by-god hypothesis. Therefore when we observe fine tuning, all else being equal, fine tuning is evidence against creation by god.

Sorry, there's no flaw in the logic here.
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Re: WL Craig: The Kalam Cosmological Argument

#2223  Postby Thommo » Jan 06, 2015 4:31 pm

Rumraket wrote:
Thommo wrote:Sorry, the conclusion doesn't follow there either.

The argument doesn't show anything about the relative probability of a God-designed universe compared to a not God-designed universe.

It doesn't purport to show that.


It does:

Rumraket wrote:Thus, given the observation of universally applicable seemingly fine-tuned laws, the probability they're due to design is less likely than they're due to chance/necessity. Isn't that brilliant?


That is the conclusion of your post - it doesn't follow, whether or not I add the word God- to the "designed" component.

Rumraket wrote:It tells us whether the particular evidence we have, ("fine tuned constants that allow life") is more probable on a designed vs non-designed universe.


That's what I said, minus the "God-" and with explicit statement of one of the pieces of background information we have (that life can exist). It doesn't follow. Comparing P(E¦A) and P(E¦B) is of itself meaningless. This is why I gave the coin example, P(coin heads up¦coin was placed heads up)=1, P(coin heads up¦coin was tossed)=0.5. This is in no way relevant or useful to ascertaining whether some coin (or coins in general) were placed or tossed. The same goes for design of universes.

Rumraket wrote:Given that all non-designed universes with life would necessarily have such constants that allow for life, the probability that we should observe such a set of constants in a universe with life if it was not designed, is 100%.

This is NOT the case on the designed by a god hypothesis. Here such a condition is only a subset of the full set of possibilities, so it CANNOT be 100%.

Therefore all else being equal and given that we observe "fine tuned constants that allow for life", this evidence is more probable on the not-designed than it is on designed-by-god hypothesis. Therefore when we observe fine tuning, all else being equal, fine tuning is evidence against creation by god.


This is fallacious. The conclusion does not follow. The restriction to the probability space is entirely ad hoc.

Rumraket wrote:Sorry, there's no flaw in the logic here.


If that were the case, finding a coin heads up would be evidence the coin was intentionally placed heads up and finding a coin tails up would be evidence the coin was intentionally placed tails up.
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Re: WL Craig: The Kalam Cosmological Argument

#2224  Postby Rumraket » Jan 06, 2015 5:51 pm

So if I understand you correctly, the issue is we can't determine the probabilities of the intentions of the designer. That basically it is concievable the designer would always choose to design a universe with some single specific set of laws like ours, making the probability of our set of laws 100% on design too?
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Re: WL Craig: The Kalam Cosmological Argument

#2225  Postby Thommo » Jan 06, 2015 6:16 pm

You can look at it that way, informally.

Think of probability like science - it's only meaningful as a model of something. We need some assumptions, which people are a bit lax at spelling out.

Formally what you need is some kind of random variable on a sample space. The argument you gave is flawed in the same way that actual fine tuning arguments are flawed - it makes assumptions about the sample space which we have no reason to make.

The fine tuning argument artificially assumes that the constants found in physical formulas (or their ratios), relating to gravity, electromagnetism can vary from what they are and that they do so with fixed probability over some interval. We don't know that they can vary, we don't know that there is anything in reality that represents the mathematical process of imagining universes being generated at random by some unknown mechanism with varying constants, although if there actually is such a process that would probably indicate a "multiverse" anyway, which the argument just ignores.

Similarly your argument is assuming that natural laws "could" generate non life sustaining universes, it makes similar assumptions about the sample space, then makes an ad hoc declaration comparing it to an assumed sample space of universes that "could" be made by a god. You will end up with weird (and untrue) conclusions because of the ad hoc nature - for example that it's "evidence" against the hypothesis that god created the universe, but not against the hypothesis that god created the universe with the intent of it sustaining natural laws (since this also would only ever 100% result in universes that sustain life, but appear to have natural laws).

In both cases this is because there is no "fitting" of the sample space to reality. There's no physical process to match the "probability" when there needs to be. It's ok to model a dice with a uniform probability on {1,2,3,4,5,6} because we can test it. What do we do if the model doesn't match that dice? We toss out the model and use a different probability distribution to reflect that the dice is "unfair", "biased" or "weighted". It's basically meaningless to talk about probability without modeling or fitting.
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Re: WL Craig: The Kalam Cosmological Argument

#2226  Postby Rumraket » Jan 06, 2015 9:58 pm

Thommo wrote:You can look at it that way, informally.

Think of probability like science - it's only meaningful as a model of something. We need some assumptions, which people are a bit lax at spelling out.

Formally what you need is some kind of random variable on a sample space. The argument you gave is flawed in the same way that actual fine tuning arguments are flawed - it makes assumptions about the sample space which we have no reason to make.

The fine tuning argument artificially assumes that the constants found in physical formulas (or their ratios), relating to gravity, electromagnetism can vary from what they are and that they do so with fixed probability over some interval. We don't know that they can vary, we don't know that there is anything in reality that represents the mathematical process of imagining universes being generated at random by some unknown mechanism with varying constants, although if there actually is such a process that would probably indicate a "multiverse" anyway, which the argument just ignores.

Similarly your argument is assuming that natural laws "could" generate non life sustaining universes, it makes similar assumptions about the sample space, then makes an ad hoc declaration comparing it to an assumed sample space of universes that "could" be made by a god. You will end up with weird (and untrue) conclusions because of the ad hoc nature - for example that it's "evidence" against the hypothesis that god created the universe, but not against the hypothesis that god created the universe with the intent of it sustaining natural laws (since this also would only ever 100% result in universes that sustain life, but appear to have natural laws).

In both cases this is because there is no "fitting" of the sample space to reality. There's no physical process to match the "probability" when there needs to be. It's ok to model a dice with a uniform probability on {1,2,3,4,5,6} because we can test it. What do we do if the model doesn't match that dice? We toss out the model and use a different probability distribution to reflect that the dice is "unfair", "biased" or "weighted". It's basically meaningless to talk about probability without modeling or fitting.

This is different from what I wrote above, you're basically taking the view that the question of fine tuning is meaningless since we don't even know whether the laws and constants could be any different from what they are.

Okay, I agree, but then the argument isn't actually logically invalid in the sense that the conclusion doesn't follow from the premises, it's just that there's an unstated foundational assumption (that they could be different) we don't know whether is true. But then it merely requires us to state that premise openly as an assumption, like:

P1: We assume the laws and constants of nature could be different.
P2: ...

?
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Re: WL Craig: The Kalam Cosmological Argument

#2227  Postby Thommo » Jan 06, 2015 11:37 pm

It's both, the argument rests on assuming certain things about a sample space and underlying probability distribution, but then compounds the issue by having a conclusion that doesn't follow anyway.

If we are told P(O¦A) is greater than P(O¦B) we can say absolutely nothing about P(A) and P(B) they could both still have any value in the range 0 <= p <= 1.

This error is compounded by the ad hoc choice of A and B to suit a specious rhetorical point (or two different opposing points, one in the fine tuning argument and one in the argument presented in this thread as a response).
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Re: WL Craig: The Kalam Cosmological Argument

#2228  Postby Rumraket » Jan 07, 2015 1:57 am

Thommo wrote:It's both, the argument rests on assuming certain things about a sample space and underlying probability distribution, but then compounds the issue by having a conclusion that doesn't follow anyway.

Both, as in both our lack of knowledge of intent and the unstated assumption about the possibility of changing the laws, is the issue?

It occurred to me that with regards to not knowing the probability distribution of intent, that issue only applies if we postulate a single specific and unknown designer. If we keep it at the level of all possible designers, there is going to be some subset of designers which would choose a different set of laws/constants(ofc assuming this is possible bla bla). So we can never arrive at a 100% score for the kind of fine-tuning we observe on just "design". There simply are designers that would choose otherwise, we need only look at ourselves to confirm this.

With these caveats, I don't see any problem with the argument.
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Re: WL Craig: The Kalam Cosmological Argument

#2229  Postby Thommo » Jan 07, 2015 6:33 am

If you don't know the probability distribution, it does rather beg the question what is meant by "probability", does it not?

Similarly excluding some unknown subset of possible designers of unknown size from a superset of designers, also of unknown size does not in fact show that the probability is less than 1, because we don't know the cardinalities of the sets involved (which is hardly surprising - we don't know anything about these sets, if they are even sets, rather than classes which are an improper domain for discussing probability in the first place). It still might almost surely be the case.

Also, we must not forget that the restriction of naturally generated universes to only those sustaining life is a choice made by an arguer for rhetorical effect, similarly the lack of restriction of gods to those gods who would choose to create via natural laws is a choice made by an arguer for rhetorical effect. Neither choice can or does reflect reality, or any real probability distribution.

If anything the argument is slightly worse than the completely fallacious fine tuning argument. It's absolutely riddled with holes. I can't understand why anyone would be able to see through one but not the other.

Mathematics is very precise and very technical. If you don't obey simple rules then you can't use terms like "probability". One is honestly better waving ones hands around and saying "it sounds about right to me" than invoking this kind of specious appeal to the authority of probability theory.

I can try and explain this on a more technical level if my attempts at speaking plainly aren't communicating the point precisely enough. I'm not sure it will be clearer, but it should be more accurate to do so.
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Re: WL Craig: The Kalam Cosmological Argument

#2230  Postby Rumraket » Jan 07, 2015 1:09 pm

Thommo wrote:If you don't know the probability distribution, it does rather beg the question what is meant by "probability", does it not?

Similarly excluding some unknown subset of possible designers of unknown size from a superset of designers, also of unknown size does not in fact show that the probability is less than 1, because we don't know the cardinalities of the sets involved (which is hardly surprising - we don't know anything about these sets, if they are even sets, rather than classes which are an improper domain for discussing probability in the first place). It still might almost surely be the case.

Also, we must not forget that the restriction of naturally generated universes to only those sustaining life is a choice made by an arguer for rhetorical effect, similarly the lack of restriction of gods to those gods who would choose to create via natural laws is a choice made by an arguer for rhetorical effect. Neither choice can or does reflect reality, or any real probability distribution.

If anything the argument is slightly worse than the completely fallacious fine tuning argument. It's absolutely riddled with holes. I can't understand why anyone would be able to see through one but not the other.

Mathematics is very precise and very technical. If you don't obey simple rules then you can't use terms like "probability". One is honestly better waving ones hands around and saying "it sounds about right to me" than invoking this kind of specious appeal to the authority of probability theory.

I can try and explain this on a more technical level if my attempts at speaking plainly aren't communicating the point precisely enough. I'm not sure it will be clearer, but it should be more accurate to do so.

But Thommo, it absolutely doesn't matter what exactly the real probability distribution is, or the total sizes of the sets.

As long as it is 100% on the one set, and less than 100% on the other, the actual sizes of the sets are irrelevant. What matters is that the probability is 100% on the one, that means what we observe will ALWAYS be the case on that hypothesis.

It doesn't matter if the other set is 10, 100 or infinitely infinite in total size, as long as the observed evidence is less than 100% of that size, it will have a probability below 100%. That is all we need to know.

=100% vs <100%. Then =100% wins, regardless of how big you make those two sets, or how much less than 100% it is.

There's nothing wrong with this argument. The question comes down to "how probable is what we observe on hypothesis X vs hypothesis Y"?

If one probability is greater than the other, and it is because it is 100% on X while it's <100% on Y, then it doesn't matter whether it's actually 99.9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999%, or 20%, on Y, what we can say then is that there is some probability it could be different on Y. This is not the case on X, so the evidence is more probable on X, because it is 100% expected on X.
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Re: WL Craig: The Kalam Cosmological Argument

#2231  Postby Thommo » Jan 07, 2015 7:06 pm

Rumraket wrote:But Thommo, it absolutely doesn't matter what exactly the real probability distribution is, or the total sizes of the sets.

As long as it is 100% on the one set, and less than 100% on the other, the actual sizes of the sets are irrelevant. What matters is that the probability is 100% on the one, that means what we observe will ALWAYS be the case on that hypothesis.


Well it rather does matter, I can only assume that you aren't familiar with the content of the link I pasted about "almost surely", which is quite understandable if you don't have a mathematical background, it's pretty counterintuitive and non trivial if you haven't seen it before, but I'll do my best to explain if you can bear with a lengthy post. My apologies if you actually are already familiar with this idea.

Just because you've ruled out some options does not in fact mean that you have 100% in one case and less than 100% in the other. This is one of the (many) problems.

Consider the following (malformed) questions:-

What proportion of natural numbers are square numbers?
What is the chance that a natural number picked at random is a square number?

So, start listing natural numbers:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ... (... means and so on to "infinity")

and their squares
12, 22, 32, 42, 52, 62, 72, 82, 92, 102, ...
equals
1, 4, 9, 16, 25, 36, 49, 64, 81, 100, ...

Now, consider the proportion of squares in each partial sequence, up to the first n terms.

1 = 100% squares
4 = 50% squares
9 = 33% squares
16 = 25% squares
25 = 20% squares
...
(this % drops asymptotically to 0 as n tends to infinity, it's given simply by the formula 1/√n for square numbers, since the kth square is exactly the k2th term, so there are k2/k squares exactly up to that point)

So, even though there are "as many" square numbers in one sense (they have the same "cardinality" because there is a square number given by k2 for each number k - a 1-1 correspondence) the proportion of squares tends to 0, and in the limit case of ALL natural numbers is 0 exactly. If we were to pick "at random" (and this is a technical error, just as in the arguments - there is no well defined uniform distribution on infinite sets in this way) the chance we pick a square number is 0 almost surely. So if we rule out picking a square, or not we can argue that the chance of picking a square is still 0. This is why the size of the sets matter - it's possible to fudge any example where the sets are infinite (and it's actually an error assuming they are sets at all in the case of "possible gods" or "possible sets of natural laws" - they aren't sets, they are proper classes) and of the same cardinality to produce any answer between 0 and 1.

Please be advised, what I've said here commits the same errors as the argument - it is not mathematically acceptable to talk about the "probability of picking a natural number at random with a uniform distribution" in this way. I've just replicated the problem to show some consequences. It's actually quite similar to an error some theist made in this thread:
http://www.rationalskepticism.org/nonth ... 0#p1797222

He goes on for a loooooooong time about how if you have two options then the chance of them happening is 50/50 - assuming a uniform distribution when there's no basis to do so and it leads to utter junk. Garbage in, garbage out.

Rumraket wrote:It doesn't matter if the other set is 10, 100 or infinitely infinite in total size, as long as the observed evidence is less than 100% of that size, it will have a probability below 100%. That is all we need to know.


And we don't know it.

Rumraket wrote:=100% vs <100%. Then =100% wins, regardless of how big you make those two sets, or how much less than 100% it is.

There's nothing wrong with this argument. The question comes down to "how probable is what we observe on hypothesis X vs hypothesis Y"?

If one probability is greater than the other, and it is because it is 100% on X while it's <100% on Y, then it doesn't matter whether it's actually 99.9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999%, or 20%, on Y, what we can say then is that there is some probability it could be different on Y. This is not the case on X, so the evidence is more probable on X, because it is 100% expected on X.


We still don't know it. Infinite sets are counterintuitive. We can rule out infinitely many options without ever going below 100%.

But this still misses the wider point that the probabilities you're comparing here don't tell us anything anyway.

Suppose there's a coin head face up on my desk (Call this event "E" = "Coin is head face up on desk"), consider two competing hypotheses:-

(A) It spontaneously appeared head face up, out of thin air, having been conjured into existence by heads up loving fairies who only ever create coins facing heads up.
(B) It was tossed and landed randomly head face up on the desk.

Notice how I've chosen these hypotheses - if A is true then there's a 100% chance the coin is head face up. If B is true then there's only a 50% chance the coin is head face up - tossed coins can land face down too!

Writing this a bit more neatly or mathematically we can say that P(E¦A)=1 and P(E¦B)=0.5; that is "Probability of E given A is 100%" and "Probability of E given B is 50%".

What does this tell us about whether we should prefer hypothesis A or hypothesis B? That is to say "what does this tell us about P(A) or P(B)?

Absolutely nothing. The probability of A is still 0. Such things do not and cannot happen. The probability of B is unknown, (the coin might have got there by some other mechanism such as being placed by a human, or having been minted there by a coin press) such things can and do happen, but we don't actually know what percentage of coins lying on desks are tossed rather than placed, although we could estimate by conducting research and fitting a distribution.
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Re: WL Craig: The Kalam Cosmological Argument

#2232  Postby Rumraket » Jan 07, 2015 8:07 pm

Thommo wrote:
Rumraket wrote:But Thommo, it absolutely doesn't matter what exactly the real probability distribution is, or the total sizes of the sets.

As long as it is 100% on the one set, and less than 100% on the other, the actual sizes of the sets are irrelevant. What matters is that the probability is 100% on the one, that means what we observe will ALWAYS be the case on that hypothesis.


Well it rather does matter, I can only assume that you aren't familiar with the content of the link I pasted about "almost surely", which is quite understandable if you don't have a mathematical background, it's pretty counterintuitive and non trivial if you haven't seen it before, but I'll do my best to explain if you can bear with a lengthy post. My apologies if you actually are already familiar with this idea.

Just because you've ruled out some options does not in fact mean that you have 100% in one case and less than 100% in the other. This is one of the (many) problems.

Consider the following (malformed) questions:-

What proportion of natural numbers are square numbers?
What is the chance that a natural number picked at random is a square number?

So, start listing natural numbers:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ... (... means and so on to "infinity")

and their squares
12, 22, 32, 42, 52, 62, 72, 82, 92, 102, ...
equals
1, 4, 9, 16, 25, 36, 49, 64, 81, 100, ...

Now, consider the proportion of squares in each partial sequence, up to the first n terms.

1 = 100% squares
4 = 50% squares
9 = 33% squares
16 = 25% squares
25 = 20% squares
...
(this % drops asymptotically to 0 as n tends to infinity, it's given simply by the formula 1/√n for square numbers, since the kth square is exactly the k2th term, so there are k2/k squares exactly up to that point)

So, even though there are "as many" square numbers in one sense (they have the same "cardinality" because there is a square number given by k2 for each number k - a 1-1 correspondence) the proportion of squares tends to 0, and in the limit case of ALL natural numbers is 0 exactly. If we were to pick "at random" (and this is a technical error, just as in the arguments - there is no well defined uniform distribution on infinite sets in this way) the chance we pick a square number is 0 almost surely. So if we rule out picking a square, or not we can argue that the chance of picking a square is still 0. This is why the size of the sets matter - it's possible to fudge any example where the sets are infinite (and it's actually an error assuming they are sets at all in the case of "possible gods" or "possible sets of natural laws" - they aren't sets, they are proper classes) and of the same cardinality to produce any answer between 0 and 1.

Please be advised, what I've said here commits the same errors as the argument - it is not mathematically acceptable to talk about the "probability of picking a natural number at random with a uniform distribution" in this way. I've just replicated the problem to show some consequences. It's actually quite similar to an error some theist made in this thread:
http://www.rationalskepticism.org/nonth ... 0#p1797222

He goes on for a loooooooong time about how if you have two options then the chance of them happening is 50/50 - assuming a uniform distribution when there's no basis to do so and it leads to utter junk. Garbage in, garbage out.

Rumraket wrote:It doesn't matter if the other set is 10, 100 or infinitely infinite in total size, as long as the observed evidence is less than 100% of that size, it will have a probability below 100%. That is all we need to know.


And we don't know it.

Rumraket wrote:=100% vs <100%. Then =100% wins, regardless of how big you make those two sets, or how much less than 100% it is.

There's nothing wrong with this argument. The question comes down to "how probable is what we observe on hypothesis X vs hypothesis Y"?

If one probability is greater than the other, and it is because it is 100% on X while it's <100% on Y, then it doesn't matter whether it's actually 99.9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999%, or 20%, on Y, what we can say then is that there is some probability it could be different on Y. This is not the case on X, so the evidence is more probable on X, because it is 100% expected on X.


We still don't know it. Infinite sets are counterintuitive. We can rule out infinitely many options without ever going below 100%.

But this still misses the wider point that the probabilities you're comparing here don't tell us anything anyway.

Suppose there's a coin head face up on my desk (Call this event "E" = "Coin is head face up on desk"), consider two competing hypotheses:-

(A) It spontaneously appeared head face up, out of thin air, having been conjured into existence by heads up loving fairies who only ever create coins facing heads up.
(B) It was tossed and landed randomly head face up on the desk.

Notice how I've chosen these hypotheses - if A is true then there's a 100% chance the coin is head face up. If B is true then there's only a 50% chance the coin is head face up - tossed coins can land face down too!

Writing this a bit more neatly or mathematically we can say that P(E¦A)=1 and P(E¦B)=0.5; that is "Probability of E given A is 100%" and "Probability of E given B is 50%".

What does this tell us about whether we should prefer hypothesis A or hypothesis B? That is to say "what does this tell us about P(A) or P(B)?

Absolutely nothing. The probability of A is still 0. Such things do not and cannot happen. The probability of B is unknown, (the coin might have got there by some other mechanism such as being placed by a human, or having been minted there by a coin press) such things can and do happen, but we don't actually know what percentage of coins lying on desks are tossed rather than placed, although we could estimate by conducting research and fitting a distribution.

Heh, funny thing is I was typing out a response to your post and while thinking about how to formulate it I realized what the flaw is. You are right of course, it is senseless to talk about the probability of the evidence on a hypotheses when we don't know the true probability distribution to begin with.

Even if the evidence is 100% probable on hypothesis X, the "true" probability of X could be a trillionth of a percentage and the true probability of Y could be the rest. :thumbup:
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Re: WL Craig: The Kalam Cosmological Argument

#2233  Postby Thommo » Jan 07, 2015 8:09 pm

Ahh cool. :thumbup:
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Re: WL Craig: The Kalam Cosmological Argument

#2234  Postby hackenslash » Jan 07, 2015 9:33 pm

Cracking post, Thommo. Bookmarked.

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Re: WL Craig: The Kalam Cosmological Argument

#2235  Postby THWOTH » Jan 07, 2015 10:11 pm

Rumraket wrote:... it is senseless to talk about the probability of the evidence on a hypotheses when we don't know the true probability distribution to begin with.

I prefer to talk about these things in terms of imaginable possibilities rather than quantifiable probabilities. To talk about the 'probability of God existing' is to fall for the soft-soap of the apologist: and if one admits that the probability of God existing is incredibly low--so low as to be almost negligible even--we're still effectively agreeing to hold the door open for God (even if it's just a chink). By such things as this apologists attempt to shift a portion of their burden.
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Re: WL Craig: The Kalam Cosmological Argument

#2236  Postby Thommo » Jan 08, 2015 2:05 am

There's a possibility that a god or gods exist, it doesn't make much sense to talk about the probability of it. There's no framework for reliably estimating an underlying distribution.

Someone might say they are 90% confident of his existence or nonexistence, but it's really quite meaningless without the underlying framework. At some point you're just affirming belief. There are statistical techniques (such as maximum likelihood estimators) that can be used to fit a distribution, but you need data for that, with sample sizes of ~100 (varying with technique). Since we only know of one universe and we don't know what "caused" it (if anything) our current sample size is 0, making any talk of probability, likelihoods and the stuff just fluff, not mathematics.

This whole area of thelogical metaphysics is just guff to be honest, and I absolutely include almost all arguments against gods in with those arguments for gods. You really can't do better than "I have no need for that hypothesis".
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Re: WL Craig: The Kalam Cosmological Argument

#2237  Postby Lowpro » Jan 08, 2015 4:56 pm

Thommo wrote:There's a possibility that a god or gods exist, it doesn't make much sense to talk about the probability of it. There's no framework for reliably estimating an underlying distribution.

Someone might say they are 90% confident of his existence or nonexistence, but it's really quite meaningless without the underlying framework. At some point you're just affirming belief. There are statistical techniques (such as maximum likelihood estimators) that can be used to fit a distribution, but you need data for that, with sample sizes of ~100 (varying with technique). Since we only know of one universe and we don't know what "caused" it (if anything) our current sample size is 0, making any talk of probability, likelihoods and the stuff just fluff, not mathematics.

This whole area of thelogical metaphysics is just guff to be honest, and I absolutely include almost all arguments against gods in with those arguments for gods. You really can't do better than "I have no need for that hypothesis".


I have a mostly similar position but one difference. If you do not have data for a position (and I mean data in a strict information stance) then you have NO POSSIBILITY. A probability can be inferred with a sample size of 1, it just will lack meaningful confidence (variation within a sample of 1 is enough). That's mathematics.

Relating that back to the cause of the universe and maybe back to your coin analogy, I'd say that your analogy does not make sense for the Universe. There is no information (re: data) for God(s) so it is not even possible. There is no data for an agent leaving the coin face up so it's not even possible to compare it to the coin flip. Now we need to know from a zero-energy universe whether it's a coin flip.
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Re: WL Craig: The Kalam Cosmological Argument

#2238  Postby Thommo » Jan 08, 2015 5:03 pm

Lowpro wrote:I have a mostly similar position but one difference. If you do not have data for a position (and I mean data in a strict information stance) then you have NO POSSIBILITY. A probability can be inferred with a sample size of 1, it just will lack meaningful confidence (variation within a sample of 1 is enough). That's mathematics.


Could you elaborate on this? All the likelihood estimation techniques (and similar) I've ever seen have requirements on sample size, 1 is never enough - to say something has a probability of 0.5 ± 0.5 is to say you have no information at all - by definition probability is already in the range 0 ≤ p ≤ 1.
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Re: WL Craig: The Kalam Cosmological Argument

#2239  Postby GrahamH » Jan 08, 2015 5:16 pm

Thommo wrote:
Lowpro wrote:I have a mostly similar position but one difference. If you do not have data for a position (and I mean data in a strict information stance) then you have NO POSSIBILITY. A probability can be inferred with a sample size of 1, it just will lack meaningful confidence (variation within a sample of 1 is enough). That's mathematics.


Could you elaborate on this? All the likelihood estimation techniques (and similar) I've ever seen have requirements on sample size, 1 is never enough - to say something has a probability of 0.5 ± 0.5 is to say you have no information at all - by definition probability is already in the range 0 ≤ p ≤ 1.


If it's happened once then you do know p > 0.
Why do you think that?
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Re: WL Craig: The Kalam Cosmological Argument

#2240  Postby Thommo » Jan 08, 2015 5:17 pm

GrahamH wrote:
Thommo wrote:
Lowpro wrote:I have a mostly similar position but one difference. If you do not have data for a position (and I mean data in a strict information stance) then you have NO POSSIBILITY. A probability can be inferred with a sample size of 1, it just will lack meaningful confidence (variation within a sample of 1 is enough). That's mathematics.


Could you elaborate on this? All the likelihood estimation techniques (and similar) I've ever seen have requirements on sample size, 1 is never enough - to say something has a probability of 0.5 ± 0.5 is to say you have no information at all - by definition probability is already in the range 0 ≤ p ≤ 1.


If it's happened once then you do know p > 0.


You don't. You know it's not impossible, you don't know that p > 0.

You might be right to criticize my saying you have absolutely no information, because you do know it's not impossible. Although I had in mind that is information about possibility, not probability. Which ties back to what I said before.
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