Monday, 9 July 2012

WLC5: Fine-Tuning Towards Ignorance

In earlier articles, I looked at William Lane Craig’s debating style (in Debatable Theism) and the logic in his “logical” arguments (in The Logic of an Apologist). In the latter, I said that I would address the content of Craig’s arguments, please check that article if you are not already familiar with the logical forms. This article addresses what I have numbered as Craig’s Fifth Argument. First a quick recap:

Craig’s Fifth Argument – Argument from Fine-Tuning for Intelligent Life
(argued during Craig-Smith – wording taken from Craig-Krauss)

1. The fine-tuning of the universe is due to either (sic) physical necessity, chance, or design.
2. It is not due to physical necessity or chance.
3. Therefore, it is due to design.

While analysing the logic, I split the argument into two stages because there is an implicit presumption regarding fine-tuning, in other words, Craig makes three assertions: that the universe is “fine-tuned”, that this fine-tuning has only three possible explanations and that two of those possible explanations are false.  By fine-tuning, Craig specifically means “fine-tuning for intelligent life” (as claimed in Craig-Krauss) and maybe even more specifically “fine-tuning for human beings” (consistent with standard theological anthropocentricism):

In recent decades scientists have been stunned by the discovery that the initial conditions of our universe were fine-tuned for the existence of intelligent agents with a precision and delicacy that literally defy human comprehension. This fine-tuning is of two sorts. First, when the laws of nature are given mathematical expression, you find appearing in them certain constants, like the gravitational constant. These constants are not determined by the laws of nature. Second, in addition to these constants there are certain arbitrary quantities which are just put in as initial conditions on which the laws of nature operate, for example, the amount of entropy in the very early universe.

Now all of these constants and quantities fall into an extraordinarily narrow range of life-permitting values. Were these constants or quantities to be altered by even a hair’s breadth, the life-permitting balance would be destroyed and life would not exist. We now know that life-prohibiting universes are incomprehensibly more probable than any life-permitting universe.

A leap in reasoning can be identified in Craig’s words here.  Even if one were to accept his argument, he doesn’t argue for “intelligent life”, he argues for “life”.  One could, however, accept that “life” is a necessary prerequisite for “intelligent life”.  Perhaps Craig should add to his argument:

Part 1

1. Premise – If life does not exist (not B), then intelligent life does not exist (not A)
2. Assertion – Intelligent life exists (A)
3. Conclusion – Therefore, life exists (B)

Part 2

1. Premise – If the universe is not fine-tuned for life (not C), then life cannot exist (not B)
2. Assertion – Life exists (B)
3. Conclusion – Therefore, the universe is fine-tuned for life (C)

Part 3

1. Premise – If the universe is fine-tuned for life (C1) then this fine-tuning is due to physical necessity, chance or design (D1)
2. Assertion – The universe is fine-tuned for life (C1)
3. Conclusion – Therefore, the fine-tuning of the universe is due to physical necessity, chance or design (D1)

Part 4

1. Premise – If the fine-tuning of the universe for life is due to physical necessity, chance or design (from D1) but is not due to physical necessity or chance (C2) then the fine-tuning of the universe for life is due to design (D2)
2. Assertion – The fine-tuning of the universe for life is not due to physical necessity or chance (C2)
3. Conclusion – Therefore, the fine-tuning of the universe is due to design (D2)

Some people will notice that this argument provides an explanation as to why the universe must necessarily be fine-tuned for life (A -> C, ie there is intelligent life, therefore the universe must be fine-tuned) and then goes on to assert that another explanation is the real one.  This is equivalent to the following argument:

Part 1

1. Premise – If “dormouse getting through a crevice”-ability does not exist (not B), then “fat dormouse getting through a crevice”-ability does not exist (not A)
2. Assertion – “Fat dormouse getting into a crevice”-ability exists (A)
3. Conclusion – Therefore, “dormouse getting into a crevice”-ability exists (B)

Part 2

1. Premise – If a barn wall crack is not fine-tuned for “dormouse getting through a crevice”-ability (not C), then “dormouse getting through a crevice”-ability cannot exist (not B)
2. Assertion – “Dormouse getting through a crevice”-ability exists (B)
3. Conclusion – Therefore, the barn wall crack is fine-tuned for “dormouse getting through a crevice”-ability (C)

Part 3

1. Premise – If a barn wall crack is fine-tuned for “dormouse getting through a crevice”-ability (C1) then this fine-tuning is due to something magical, something random or something physical (D1)
2. Assertion – The barn wall crack is fine-tuned for “dormouse getting through a crevice”-ability (C1)
3. Conclusion – Therefore, fine-tuning of the barn wall crack is due to something magical, something random or something physical (D1)

Part 4

1. Premise – If fine-tuning of the barn wall crack is due to something magical, something random or something physical (from D1) but is not due to something random or something physical (C2) then fine-tuning of the barn wall crack is due to something magical (D2)
2. Assertion – Fine-tuning of the barn wall crack is not due to something random or something physical (C2)
3. Conclusion – Therefore, fine-tuning of the barn wall crack is due to something magical (D2)

This might not be completely clear, especially for readers who are unfamiliar with fat dormice.

Part 1 is completely true, a fat dormouse is less likely to get through a crevice than a standard dormouse – but if a fat dormouse can get through, then some sort of dormouse can get through.

Part 2 is not necessarily true.  Barn walls are not “tuned”, let alone “finely-tuned” with dormouse entry requirements in mind.  Now we humans do make barn walls, this is true, but we don’t design the cracks with any intention at all – they just appear.  A fat dormouse, Chubby Loir, who passes through a barn wall crack to escape the attentions of Tiddles could pause a moment and ponder about the munificence of the being that had made that crack, perhaps reflecting on the fact that the crack appears to have been created just for him, indeed it appears "finely-tuned".

If the crack were smaller, then Chubby Loir would not have been able to squeeze his fat little dormouse body through. If the crack were larger, then Tiddles would have been able to squeeze through.  At this point, the rational among us realise that despite appearances, the crack was not designed to permit Chubby Loir's narrow escape (nor was it designed by an evil barn builder for the express purpose of frustrating Tiddles).  The existence of the crack was just a happy coincidence.  Note however, that if the crack did not exist, then Chubby Loir would not have been able to pause and consider, he’d be too busy pondering the whole being eaten experience.

The same applies to us: we could not be here, pondering how great it is that the universe seems to be finely-tuned for life, if it weren’t at least sufficiently well-tuned.  The fine-tuning of the universe (such as it is) is a prerequisite for us to be here pondering.  Even if there might be staggeringly huge odds against us being here (assessed well before life begins to develop), those odds no longer apply once we are here.  The probability of me having won the lottery, once I have won the lottery, is 100%.  The probability of Tiddles having being named Tiddles is 100%.  Similarly, the probability of the universe having been sufficiently well-tuned to produce me (given that am sitting here typing these words) is 100%.

Parts 3 and 4 are where Craig comes into his own, which is no surprise since together these constitute his explicit argument.  Let’s recap again, Craig’s argument here is (abbreviating it a little):

1. The fine-tuning of the universe is due to either something that isn’t design - or design
2. It is not due to something that isn’t design
3. Therefore, it is due to design

Honestly, that’s his argument.

He barely touches this argument in Craig-Smith and while he gives it a bit more attention in Craig-Krauss (see above), he doesn’t provide much in the way of support.  Oh well, I’ll just have to do his work for him (yet again).  Craig argues that there are two fine-tuning aspects: constants and initial conditions.

The first shall be last and the last shall be first, so let us look at initial conditions first.  Craig argues that “there are certain arbitrary quantities which are just put in as initial conditions on which the laws of nature operate, for example, the amount of entropy in the very early universe”.  This is just false.  The “quantities” aren’t arbitrary, they are the “quantities” that current theories suggest.  Since the question is not completely resolved yet, the quantities, arbitrary or otherwise, could be completely wrong.

The standard cosmological model could be wrong.  We keep finding that the models are not quite right, which is why things like dark matter, dark energy and dark flow keep getting added.  Pointing to a particular model that is in use today and saying “This might not be completely true” isn’t saying anything new.  We all know that current models are almost certainly wrong in some way.  Nobody really knows what the initial conditions were so Craig has nothing on which to base his argument.  It’s a complete non-starter (unlike the Big Bang).

And now … constants.  Craig picks on the gravitational constant.  I know, it's embarrassing.  This choice just highlights his ignorance.  The fine-tuning argument to the extent that it works, works with dimensionless fundamental constants, such as the fine structure constant.  It doesn't work with physical constants, all of which have dimensions, and which tend to resolve to a value of 1 when expressed in terms of natural units (for example Planck units).

In terms of Planck units, the gravitational constant is 1, the speed of light is 1, vacuum permeability is 1, vacuum permittivity is 1 and (perhaps unsurprisingly) Planck’s constant is 1.  The apparent values of these constants are merely the consequence of having unnatural units, they are the results of exchange mechanisms similar to the exchange rate between two currencies.  So, perhaps we should just pretend that Craig didn't ignorantly choose the gravitational constant as an example.

Maybe we could grant him the fundamental dimensionless constant required by the standard cosmological model: the cosmological constant – which is currently accepted as the simplest solution to a problem with the model.  The problem here, again, is that this is a simple solution to the problem, but might not actually be the actual solution.  It's entirely possible that this constant will not be necessary once the theory is developed further, making it another bad choice.  We won't force poor choices on Craig.

Perhaps we could use one of the 23 fundamental dimensionless constants required by the complete standard model of particle physics.  However, yet again, if the standard model of particle physics is wrong (or rather incomplete) and replaced by string theory, then the requirement for some of the constants disappears and the remainder are merely consequences of something else.  These would also be poor choices.

Leaving aside theoretical physics and cosmology which could quite possibly be wrong and therefore can’t be used in a fine-tuning argument, or at least not validly, we have (at least) two constants remaining.

The best known dimensionless constant is the fine structure constant.  This is an exciting one for “fine-tunists” because firstly, it is close enough to 1/137 to get numerologists into a bit of a dither (Eddington argued that it was precisely 1/136, then 1/137 once a better value of the constant was calculated), and secondly, if this value was different by 4%, then stellar fusion would not produce carbon.  The problems are as follows:

•  The fine structure constant might not actually be constant.
•  The fine structure constant is close to 1/137, but not actually 1/137.
•  A permissible variation of 4% is not “fine-tuning”, it could be argued to be “coarse-tuning” but even that is dependent on the range of possible values available to you if you are constructing a universe from scratch, a range about which we have absolutely no information.

The fine structure constant is related to the electric charge carried by a proton, which is a fundamental physical constant – α = e-squared / ((4πε-sub-0).h-bar.c).  In natural units, these all resolve to unity (that is a value of 1) with the exception of α, 4, π and e.  In other words, the constant is just a reflection of how much charge a proton can carry (e).   Sure, there are consequences if it were different, but it’s just the nature of a proton that it carries that much charge.

Even if Craig’s arguments worked and he could support the idea that the universe looks like it could, possibly, have been designed, he still has failed to show why chance and physical necessity aren’t options.  His assertion is completely unsupported and should be watered down accordingly.

At bottom, Craig has here another variation of the Cosmological Argument from “God Did It”, which is fundamentally a variation of the Cosmological Argument from First Cause, both of which we can safely dismiss.  The fine-tuning argument certainly sounds more impressive and dimensionless constants are sufficiently poorly understood to provide enough space to hide a small to medium god, but the lack of knowledge and understanding is far better addressed by saying “We simply don’t know why certain characteristics of the universe are just the way they are, but that they are the way they are is obviously the case because … well, they are the way they are!”

I almost forgot to reword Craig’s argument!

1. The coarse-tuning of the universe is due to either (sic) physical necessity, chance, or design, or something that we haven’t thought about yet.
2. It might not be due to physical necessity or chance.
3. Therefore, coarse-tuning of the universe might be due to design, or something that we haven’t thought about yet – or, alternatively, it might be due to physical necessity or chance.

The upshot of this seems to be that via Craig’s argument we arrive at a point where we know less than when we started.