Astrophysical Fine Tuning, Naturalism, and the Contemporary Design Argument

Abstract

Evidence for instances of astrophysical ‘fine tuning’ (or ‘coincidences’) is thought by some to lend support to the design argument (i.e. the argument that our universe has been designed by some deity). We assess some of the relevant empirical and conceptual issues. We argue that astrophysical fine tuning calls for some explanation, but this explanation need not appeal to the design argument. A clear and strict separation of the issue of anthropic fine tuning on one hand and any form of Eddingtonian numerology and teleology on the other, may help clarify arguably the most significant issue in the philosophy of cosmology.

Acknowledgements

Many thanks to Ric Arthur, James W. McAllister, and two anonymous referees for a number of very useful criticisms and suggestions.

Notes

[1] Terminological points: we refer to the ‘Design argument’ with a capital to underscore the fact it invokes the intentions of a deity to distinguish it from possible confusion with the sorts of design that might be the product of some non‐intentional process such as Darwinian natural selection. Furthermore, in this paper, we use ‘naturalism’ in the ontological sense that our universe has no deistic designer; we do not use it in its methodological sense in which ‘naturalism’ might mean the adoption of the scientific method.

[2] Of course, we need also to accept the fundamental importance of primes in the number theory which by definition holds in both our actual universe and the PNU.

[3] On occasion, we will use the singular ‘anthropic principle’, although we acknowledge that this glosses over the fact that there are a number of different anthropic principles. See Bostrom (2002), chapter 3, for some discussion.

[4] It may be possible for other forms of intelligent life to develop under radically different conditions, e.g. science fiction is replete with intelligent beings of ‘pure energy’, there is a famous idea of Robert Forward about beings based on the nuclear force instead of electromagnetism, Fred Hoyle’s ‘black clouds’, etc. Anthropic thinking is concerned with the conditions necessary for life as we empirically know it to develop.

[5] It is perhaps worth mentioning here that in our estimation, Klee is one of the best recent critics of astrophysical fine tuning. Although we are critical of some of Klee’s results, we are in agreement with the general position of his article that serious work on astrophysical fine tuning requires studious attention to the empirical details. Klee has shown that some claims made by early researchers on behalf of ‘mathematical fine tuning’ are definitely not supported by contemporary empirical research. On the other hand, since Klee enjoins us to raise the bar on this research (not to engage in what he terms ‘mathematical sharp practice’), it does not seem inappropriate to apply this same standard to his results.

[6] It is not beyond reason that such an understanding is present, for instance, in the passage quoted above from the summary of Oberhummer, Csoto, and Schlattl (2000); note the locution ‘in our universe’.

[7] The difference between the average absolute magnitudes of stars (or galaxies or any other similar sources) in magnitude‐limited and distance‐limited samples, discovered in 1920 by K. G. Malmquist.

Additional information

Notes on contributors

Mark A. Walker

Mark Walker is a Research Associate at Trinity College, University of Toronto, and an assistant professor at the Department of Philosophy, McMaster University, Canada.

Milan M. Ćirković

Milan M. Ćirković is a Researcher at the Astronomical Observatory Belgrade, Serbia and Montenegro.