The first of the arguments for the reality of God proposes that God must be the Creator of the world, because it is beautiful. Finding a watch on the beach is tantamount to knowing that somewhere there is (or at least was) a watchmaker.{1} Similarly,the world (and in particular life) is simply too complex to have come about of itself. Before it became clear that Darwinian Natural Selection might effectively favour the growth of complexity and diversity over geological time, this argument was a powerful one. Nowadays it is generally out of favour; though in a more abstract form it is has re-emerged as “The Strong Anthropic Principle”.
The uncertainties in Darwinism
It should be noted, however, that the fact that Natural Selection could in principle drive evolution, does not mean that in practice it has done so. Darwinism is constituted of two independent elements. These are: first, the process of mutagenesis, by which occasional mistakes in gene transcription give rise to variations which affect the constitution of a living creature; and second, the natural selection of favourable genetic variations in accordance with the principle of “the survival of the fittest”. Both of these elements have to be up to the task for Darwinian evolutionary theory to be in fact the explanation of the origin of species.
The background rate of mutation
For Darwinism to be established as a complete explanation for evolution, it would first have to be shown that the historic rate at which random mutations appeared was large enough to provide a sufficiently diverse gene pool for natural selection to work on.
The main evidence in favour of this hypothesis is the simple fact that evolution has taken place; but this observation simply begs the question. It supports nothing beyond a viciously circular argument. Accepting that evolution has occurred does not force one to grant that any particular mechanism is responsible and so does not establish that the historic mutation rate is large enough to account for evolution. What is certain is that the preponderance of mutations are either harmful or neutral in character. Only a very small minority are at all beneficial. Moreover, the question at hand is complicated by two other, possibly linked, considerations.
The first complication is that throughout geological time a sequence of catastrophic events has impacted on the path of evolution in dramatic ways. Whether these events impeded or provoked the diversification of life and its general increase in complexity is a moot point; as is whether they can properly be described as random, rather than disastrous – or even providential.
The second complication is that the fossil record makes it clear that the rate of evolution (however this might be measured) is not at all steady. In particular, there was a tremendously long period (between about four thousand million years ago and about one thousand million years ago) when life on earth was confined to the oceans as single-celled organisms. Only when life dragged itself onto the land did the headlong rush into diversity begin.
It is possible that the impetus behind the aboriginal step-change in the rate of evolution was itself some quasi-catastrophic event, such as a nearby giant star going “super-nova” and irradiating Earth with high levels of mutagenic radiation. Alternately, it may have been caused by the “seeding” of the biosphere with extra-terrestrial viruses as a result of comet impacts; or even by the purposeful intervention of some extra-terrestrial intelligence! Failing the construction of a time machine, it is implausible that we shall ever have a definitive explanation for the irregular and erratic progress of evolution.
It might seem that the way to decide whether the background rate of mutation is enough to explain the observed facts of evolution would be to set up an experiment in which it was certain there were no extraneous influences and observe the rate of evolutionary change. Unfortunately, this is fraught with difficulty.
First, it would be entirely impracticable, because the kind of evolutionary change one is concerned with is only known to occur on a time-scale of ten thousand years or more. Any attempt to extrapolate from smaller changes would be crucially dependent on so many assumptions as to be worthless. A recent experiment on the bacterium Escherichia Coli, where mutagenesis was observed in the laboratory over twenty thousand generations proved to be highly problematic.{2}
Second, it would be impossible to be sure that one had excluded all extraneous influences. After all, if one is trying to show that “providence isn’t involved in evolution” one would have to definitively exclude providence from the experiment – which is something of a tall order! As an alternative, it might eventually be possible to model the process theoretically; but the level of complexity of biological systems makes this a truly daunting prospect. Pending the success of either of these investigations, one must conclude that whether or not the background rate of mutagenes is is sufficient to explain evolution is, and must always remain, an open question.
Consistency of progression
It is far from certain that, left to itself, natural selection could ever produce the wide range of highly distinctive creatures that are now found to exist. It might do so in theory; but whether it did do so in practice one simply cannot say – except as a matter of faith. It might be the case that no matter what the rate of background mutagenesis is, the cumulative effects of random changes can only be “much of a muchness” rather than the development of dramatic difference, as is in fact observed.
There is no evidence that evolution is directed towards any particular kind of outcome. Its only teleos seems to be that of life itself: namely survival. There is no good reason to believe that evolution is in any way about the production of more complex or sophisticated or intelligent creatures from ones that are less so. In fact, evolution sometimes produces creatures which are degenerate compared to their precursors; such as blind cave fish.
The process of evolution, as we know it, is profligate and wasteful; featuring mass extinctions and many singularly peculiar creatures. The fact that many dead-ends and catastrophic events feature in the evolutionary story makes it clear that if the process is in any way directed by an extrinsic teleos, it is not directed as the human mind generally conceives direction. The kind of “designer” that still might be at work would be more of an artist or poet, who makes use of pre-existent random things, incorporating them into their work in accordance with an emerging idea; rather than an engineer, who seeks to impose a rigid pre-existing plan on the raw material of the physical world.
The Anthropic Principle
Given that I exist, I must of necessity do so in a Cosmos which is suitable for my existence. This is called the Weak Anthropic Principle. It follows from this truism that I must observe that the Cosmos is suitable for my survival. Those aspects of cosmic order which appear tuned to allow for our specific kind of life require no additional rationale. Values for the constants of Physics incompatible with the formation of carbon based macro-molecules would only rule out our own type of life, not life in general. Even if the laws of Physics were very different, then although I would not exist, some other form of life might well do so and be asking questions like “why is the Cosmos just right for me?” in my stead.
However, I shall next argue that if any of the laws of Physics were to be changed even slightly, then no life of any kind could have come into being. This contention is called the Strong Anthropic Principle. If it is true, it is indisputably queer that the Cosmos is suitable for my existence in such a singular manner and it would seem that the Universe had to be carefully engineered in order to allow for the emergence of life. Prof. Paul Miller puts the case as follows:
Although the specifics of carbon Chemistry… may not be necessary for life… a living being must contain organized complexity, or information… [which] requires… a local decrease in entropy. Entropy is… the disorder in a system, and… entropy always increases… cups fall and shatter, they do not coalesce and jump back onto their saucers. More importantly, without sustenance and breath, bodies die and decay, while corpses do not come back to life. A living being with the ability to ask the question “why am I here?” must contain an incredible amount of order to be able to frame such a deep, information filled thought, whatever kind of Chemistry or Physics underlies the being. So the question is, “what kinds of Universe could allow such order to arise?” If the answer is “just about any” then we should not be so surprised about our Universe – the right, well suited type of order would arise to fit the environment in any Universe. However, if the answer is “almost none”, then we do need to question why the Universe is so special.{3}
Of course, if there are an infinite number of Universes, each with its own distinctive physics, then there is nothing to explain. No matter how unusual it is for a Universe to be “life friendly”, those few which are so will give rise to life, and whenever life achieves self-consciousness it will start writing books just like this one.
This possibility is known as the Multiverse Hypothesis.It conflicts with the hope of many theoreticians that only one physics is coherent. If its laws featured no arbitrary parameters, then everything would be explained – except for the fundamental question “Why is there anything at all?” It would be truly remarkable if the only possible set of laws and fundamental constants is exactly the one which we know gives rise to life in such a precarious manner. This would suggest that logic itself indirectly necessitates life. Of course, the prologues of both Genesis and John’s Gospel might be construed to present exactly this doctrine.
On the Multiverse account of reality, one avoids invoking an infinite Creator as an explanation for the Cosmos at the expense of postulating an infinite (or extremely large) set of worlds. Arguably, this set would together constitute God under another name. It is, however, possible to make the Multiverse hypothesis somewhat more palatable, as Miller describes:
Many cosmologists are attempting to find what explanation they can within science, in preference to invoking a Creator… the ripples left on the cosmic background radiation… provide strong evidence for a period of… exponential expansion… in the first 10-33 seconds of the Universe’s existence. If such an era existed, there is no reason [to think] that the Universe we observe is all that condensed… There could be a plethora of… sub-Universes, that are completely unobservable to us… it is not so surprising that one of a multitude of sub-Universes happens to have the right conditions for life.
As someone suspicious of the application of probability theory to reality, I cannot resist pointing out that this argument is all about how likely it is that the Cosmos is exactly how it is. Given that the Cosmos is in fact what it is; we know the probability(in one sense of the word) that it is so; namely unity! Only if one can legitimately conceive of a set of equally likely alternatives (and this necessitates knowledge of a symmetry of some unknown system which is supposed to underlie all possible Universes)can one start to ask questions such as “What proportion of all possible Universes are compatible with life?”
String theory is typically put forward to serve as the underlying system. This unsubstantiated theory has the property of being compatible with a large number of highly diverse types of space-time. Hence, if every possible variant of space-time is arbitrarily taken to have the same basic probability and to have somehow occurred, then “It is not so surprising that one of a multitude of sub-Universes happens to have the right conditions for life.” However, what is being done here is to explain a finitely surprising particular (that is, the existence of sentient life) in terms of an infinity of unsurprising particulars. It is not at all clear to me that this is a worthwhile enterprise. Miller continues:
It is well known that all life on Earth (barring the strange sulphurous life arising around deep-sea volcanic vents) is ultimately dependent on the inflowing energy from the sun. The sun is an average star, and, like all stars, can provide the power for life, by providing vast amounts of energy (as heat and light) at very low entropy (from a small region much hotter than the rest of the Universe). Hot spots, such as stars, are necessary to allow any form of organized complexity to arise. Living things must all take in low entropy (hot or organized) energy and release it at high entropy (useless waste heat) in order to increase or at least maintain their internal information. The “hot spots” which allow any living being to survive, must also be there for it to evolve, so must remain stable over a large period of time, compared to typical physical processes in the life cycle of the being. Now, in our Universe there is a specific resonance in the nuclear reaction process, which enables stars to burn at all, and endure for the billions of years that have been necessary for life to develop. In a Universe almost the same as ours, but perhaps with a slightly different electron mass, the resonance would not occur, stars would not shine, and the Universe would be dark, dead and dull.{4} There is a multitude of similarly finely tuned properties of our Universe… The delicate balance between the original expansion of the Universe and the gravitational attraction, which tends to pull everything back together, ensures that the explosive debris from one star can arrive in the vicinity of another star which forms separately. All life on Earth is made from atoms of debris from the first star, and relies on heat and light from the second star, namely our sun. In a gravitationally stronger Universe, the first star would swallow the second, while in a… more spread out Universe, the debris would never reach another star.
This is a telling argument. Darwinianism can’t help here. Even if the laws of Physics could mutate, it is difficult to see how natural selection could operate. Of course, it might just be that the Cosmos is a self-consistent solution. The idea being that the Cosmos was created (or the laws of Physics at least massaged) by gods that evolve within the Cosmos and then travel back to the beginning of time to ensure that the Cosmos starts off just right. Miller expresses a related idea, more prosaically:
A similarly untestable possibility put forth by scientific skeptics is that the Universe is really infinite in time,and just bounces in and out of big crunches and big bangs. There is supposedly a new set of laws of Physics each time round (though, this is rather implausible in my view, as the new mashed-up fundamental laws must always lead to another bouncing Universe, without being specifically tuned!)
Miller concludes as follows:
While scientific skeptics deny the Strong Anthropic Principle, many theologians and religious scientists embrace it, as it points to a Creator who stimulates life and enables us to flourish. The uncovering of such a fertile Universe, which is so clearly conducive to beauty, encourages process theologians, as it appears that the Universe follows a very thin line between rigid order and incoherent chaos. Other religious thinkers remain wary of the whole argument, and following the “contrast” viewpoint, are loathe to incorporate any scientific evidence, which may be later reinterpreted, in their vision of God. As the “many Universe” theories are not completely out side the realms of falsifiable evidence, it is perhaps right to be patient before hailing the fine-tuning as proof of God. Nevertheless, I for one do not cease to be amazed by the transcendent beauty inherent within the laws of nature. These will always speak to me of the nature of God.
Personally, I am mostly on the side of the “other religious thinkers”. I am suspicious of any version of the Argument from Design and find the arguments from Contingency and Value (presented later in this chapter) more satisfactory. Nevertheless, Hoyle did have a point when he wrote:
Would you not say to yourself, “Some super-calculating intellect must have designed the properties of the carbon atom, otherwise the chance of my finding such an atom through the blind forces of Nature would be utterly minuscule.” Of course you would… A common sense interpretation of the facts suggests that a super intellect has monkeyed with Physics, as well as with Chemistry and Biology, and that there are no blind forces worth speaking about in Nature. The numbers one calculates from the facts seem to me so overwhelming as to put this conclusion almost beyond question. [F. Hoyle “The Universe Past and Present Reflections.” (1981)]
Subsequent to Hoyle’s discovery, other instances of the fine tuning of Physics have come to light.{5} Perhaps the most significant of these is that relating to the “zero-point energy” of the vacuum.
Any simple quantum mechanical theory of the vacuum tends to the strange conclusion that empty space has a extremely large “zero-point energy” density; whereas common experience tells us that the vacuum has, in fact, a density pretty close to zero. Now, for a long while it was thought that the density of the vacuum was precisely zero and once it was realised that quantum mechanics did not allow this to be true it was taken for granted that some fundamental symmetry of Physics would eventually be found which forced some other antagonistic phenomenon into exactly cancelling out the huge “zero-point energy” of the vacuum. This was a plausible hope, though it was highly unsatisfactory that no definite way of effecting such a cancellation was forthcoming.
More recently, it has become accepted that the best way of accounting for certain astronomical observations is to hypothesise that the Cosmos is pervaded by “dark energy” which tends to cause it to expand at an ever increasing rate. The simplest way to account for this dark energy is to identify it with the zero-point energy of the vacuum. Unfortunately, the vacuum density compatible with the astronomical observations is about 10^120 times smaller than the simplest finite estimate of the vacuum’s zero-point energy. This huge discrepancy has been called “the worst theoretical prediction in the history of Physics!”{6}
A number like 1/10^120 is difficult to stomach. It represents neither an exact cancellation, which might have a basis in some mathematical symmetry; nor an accidental cancellation. The idea that two independent contrary effects might cancel to this degree of precision is unbelievable. Hence, the ratio 1/10^120 has the appearance of a contrivance or purposeful choice, in the same way that Hoyle’s nuclear resonance does. Hence, it can be taken as evidence in favour of the Cosmos having an Intelligent Designer.
On the other hand, this ratio can also be taken as evidence in favour of the Multiverse hypothesis; for if this hypothesis is true, then most Universes with intelligent life can be expected to be only marginally suitable for the evolution of such life – simply because there must be many more ways of arranging things so that they are “just about OK” than so that they are “exactly right”. Now, it is presently thought that galaxy formation would be impossible if the dark energy density was as little as ten times larger than in fact it is. Hence, the level of supposed cancellation is close to the worst level acceptable; as would be expected if the Multiverse hypothesis were true.
However, this argument is not altogether convincing; as our theories of galaxy formation may themselves be too dependent upon our experience of the Universe being the way that it is. Clearly. if we lived in a Universe with a dark energy density ten times larger than in fact it is, we would know that it was possible to discover a theory of galaxy formation which allowed the Galaxy we existed in to have been formed in the presence of this higher level of dark energy density. This fact would make us persist in our theoretical endeavours until we had found such a theory. Because we don’t live in such a universe, we have no motive to set about discovering this theory, if it exists; so we are liable never to find it but rather to conclude, out of conceit, that it doesn’t exist.
1. W. Paley “Natural Theology” (1802)
2. J.E. Barrick et al “Genome evolution and adaptation in a long-term experiment with Escherichia Coli” (2009)
4. Sir. F. Hoyle was the astrophysicist who discovered this fact. He was an atheist at the time, but subsequently became a convinced theist.
5. P. Davies “The Goldilocks Enigma” (2006) Chapters 7 & 8.
6. P. Hobson et al “General Relativity: an introduction for physicists” (2007)
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