b) The Anthropic Principle (AP)

The term ‘the anthropic principle’ was coined by Brandon Carter in 1974in bring together various ‘large number coincidences’ about the universe which had received scattered attention throughout this century. Although formulated in a variety of ways, in its strongest form the AP poses the following question: How are we to explain the fact that the values of the fundamental constants of nature (e.g., the speed of light, Planck’s constant, etc.) and the form of the fundamental physical laws are precisely what is needed if the evolution of life is to possible? Estimates have been made which suggest that if the values of the natural constants differed from their actual values by one part per million, it would have been impossible for life to have evolved in the universe.

To some, then, the universe seems ‘fine-tuned’ for life, suggesting a cosmological version of the design argument for God.Opponents have deployed a variety of “many worlds” arguments. Perhaps there are many universes, existing as distinct domains of one actual universe or as other actual universes disconnected from our own, each with different values of the natural constants, perhaps even different physical laws.It is then a tautology that we evolved in that particular universe whose conditions are the prerequisites for life.

The following represent positions on the AP.:

i) On ‘design’ arguments: John Barrow and Frank Tipler published a massive study of the AP as a design argument, including its historical background and philosophical development, its relation to astrophysics, quantum mechanics and biochemistry. They also offer speculative implications for life in the universe, particularly in the far future,which Tipler later discusses in detail (see Part 2, E, 3 below). John Leslie has collected and analyzed numerous forms of the argument. His overall evaluation is that, “while the multiple worlds hypothesis seems to me impressively strong, the God hypothesis is a viable alternative to it...Contemporary religious thinkers (often assume that ) design arguments can have absolutely no force. I hope to have shown that philosophy has demonstrated no such thing.”Leslie then adopts a Neoplatonic view of God as an aesthetic/ethical principle. Ernan McMullin, however, after pointing out the connection between fourteenth-century debates on contingency and the AP, stresses the problems in claiming that the AP is an ‘explanation’ even in the context of Christian presuppositions, the basically teleological character of the AP mode of reasoning, and its vulnerability to theory-change in science.

After a careful reading of contending arguments, Mark Worthing cautions that, given the cosmological evidence, the ‘designer’ of the universe need not be the Creator of God of theism: both a divine demiurge, including the universe per se (as Dawkins suggests), or an emerging divinity, as the Barrow/Tipler model requires, takes into account the empirical evidence of design. In essence, unaided reason is a limited approach to God.According to Barbour, the theological implications of the AP as a modern design argument are minimal: “...even if the arguments are accepted, they would not lead to the personal, active God of the Bible... but only to an intelligent designer remote from the world... Natural theology can show that the existence of God is a plausible hypothesis, but (this is) far removed from the actual life of a religious community.”

ii) On ‘many worlds’: Though not supporting ‘design’ per se, Bill Stoeger has argued against the kind of empirically unwarranted mathematical extrapolations used to support the ‘many worlds’ position. Admittedly the mathematical structure of theoretical physics and cosmology can be seen as describing not just our universe but an ensemble of universes. Still, unless one is a Platonist, the fact that such an extrapolation is possible mathematically does not entail that these universes necessarily exist. The crux of Stoeger’s argument is that the efficacy of nature lies in nature and not in the laws we say it ‘obeys’ (i.e., science is descriptive, not prescriptive). Ultimately the existence of the universe is unanswerable by science.

iii) On the AP in theology: As early as 1979 Peacocke gave the AP an indirect but important role within his discussion of the doctrine of creation, using the metaphors of God as elaborating a fugue and as a bell-ringer sounding the changes.George Ellis has explored what he calls the “Christian Anthropic Principle,” combining design perspectives with a theology of divine omnipotence and transcendence and drawing from William Temple. Fine-tuning leads not to evidence for God; instead it is seen as a consequence of what we mean by God as the Creator of life whose goal is the “eliciting of a free response of love and sacrifice from free individuals.” This approach then leads to five implications, including the orderliness of the universe that allows for free will, God’s self-limitation in giving up intervention, the possibility of revelation, the existence of pain and evil and God’s hiddenness in the world as entailed by the impartiality of the laws of nature. Nancey Murphy,however, treats Ellis’ thesis as an argument for God. She reconstructs Ellis’ paper using a Lakatosian structure in order to show that theology can be seen as a science and that cosmological fine-tuning can serve as an auxiliary hypothesis in such a theological program. The Lakatosian ‘novel fact’ in the Temple-Ellis approach is that God designed the universe to be both law-governed and fine-tuned; the former, being irrelevant to Temple, is thus “weakly novel”.In further writings, Ellis argues that science “is not designed to deal with ultimate causation.” Instead we need take into account both scientific and ‘broader’ views. A similar approach was taken by Murphy and Ellis in further work involving ethics and kenotic theology (see Section 2,E,2 below).

Richard Swinburne has drawn on the AP to augment his ongoing program to defend ‘the case for theism.’He concludes, “I believe (the evidence here and elsewhere) render the existence of God significantly more probably than not.”According to John Polkinghorne, the AP raises a profound opening for natural theology by pointing to “the finely tuned balance in the laws of nature, enabling the evolving history of the universe to achieve its astonishing fruitfulness...” It also offers a “promising area of interaction” with other world religions.

In my view, the AP does not serve primarily as a basis for an argument for God. In fact, one can see elements of both contingency and necessity arising dialectically in both sides of the ‘design / many worlds’ debate and leading to differing levels of abstraction and suggestions of further design and many worlds.The AP can, however, play a fruitful role if incorporated within ongoing constructive theology, illuminating its inner meaning and suggesting connections between theological topics we might not otherwise have recognized. For example, it helps make explicit the subtle implications of Pannenberg’s famous dictum, “the universe as a whole and in all its parts is contingent.” The AP also underscores the key role that Planck’s constant plays in the particular overall structure of the universe, a role that a theology of creation ex nihilo would need to take seriously. The same constant may be a critical factor in compatibilist discussions of free will and thus for theological anthropology: for us to act, nature at the physical level must, arguably, be indeterministic.It also functions pivotally in some approaches to non-interventionist divine action, particularly in the context of theistic evolution (see Part 2, C, 2 below).

Contributed by: Dr. Robert Russell