Over the years philosopher Robin Collins has developed an argument that is distinct from but complementary to the one Jay Richards and I offer in The Privileged Planet — which is out now in a new updated edition. Collins is a professor at Messiah College in Pennsylvania and is well-known for developing modern arguments for theism based on the fine-tuning for life of the physical constants and laws and the cosmological initial conditions. He also has a strong background in physics. I’ve known Robin for about 25 years.

A Symposium at Yale

In November 2000 we each presented at the “Science and Evidence for Design in the Universe” symposium at Yale University. This was my first presentation of what would later become the “Privileged Planet” hypothesis; at the time, I was still adding to my folder of examples to make what would become the cumulative case argument in The Privileged Planet. We had not coordinated our presentations prior to the symposium. Yet, we each reached similar conclusions: the universe is fine-tuned to facilitate scientific discovery. I argued from the empirical sciences, and Robin made his case from theoretical physics. After our talks, we marveled at the convergence of our ideas.

Since then, Richards and I published the first edition of The Privileged Planet in 2004, and Collins started formalizing his ideas in 2010. In 2016 the John Templeton Foundation awarded him a grant to explore how the universe is fine-tuned for scientific discovery. One of the outcomes of his research was a chapter (“The Fine-Tuning for Discoverability”) in the 2018 book Two Dozen (or So) Arguments for God: The Plantinga Project. To the best of my knowledge, this has been his only published work on the topic to date. He has given public lectures on the subject, one of which can be seen here:

Note, in this lecture Robin presents a more developed version than the one in the book chapter. The following is a short summary of Robin’s argument based on his book chapter.

Summary of Robin Collins’s Argument

Robin begins by contrasting his argument with the more familiar anthropic fine-tuning argument, which posits that the fundamental constants and laws of physics must be precisely set for life to exist. His new argument focuses, instead, on the apparent optimization of physical parameters for scientific discovery. He introduces the concept of the “discernable-discoverability-optimality range” (DDOR) for various fundamental physical parameters. This is the range of values that seems optimal for allowing humans to discover and understand the laws of nature. Importantly, this range is often much smaller than the range that would allow for life (the anthropic range).

Robin gives several examples of fine-tuning for discovery:

1. Low entropy of the universe: While only a small region of low entropy is needed for life, the entire observable universe has low entropy. This allows us to observe distant galaxies and discover cosmological expansion, and that the universe has an age.
2. Fine-structure constant (a): If a were slightly larger, open wood fires would go out, inhibiting technological development. If smaller, it would negatively impact tools like microscopes and electric motors.
3. Baryon to photon ratio: This parameter is set to maximize the intensity of the cosmic microwave background radiation, an important tool for cosmology.
4. Particle physics parameters: Various parameters in the Standard Model of particle physics, such as particle masses, appear to be set at values optimal for probing the model and potentially discovering deeper physics.

Addressing Objections

Like any good philosopher, Robin addresses several possible objections to his argument:

• Discoverability Selection Objection: This objection posits that we shouldn’t be surprised to find parameter values allowing for discovery, as we wouldn’t be aware of domains we couldn’t discover. However, this objection can be countered in several ways. First, it’s possible to be aware of a domain’s existence without having the ability to study it in depth. More importantly, the argument isn’t just that the parameters allow for discovery, but that they appear to be optimized for it. The parameters don’t merely fall within a broad range permitting discovery; they lie within much narrower ranges (DDORs) that seem to maximize our ability to investigate and understand. This level of apparent optimization goes beyond what a simple selection effect would explain. To illustrate, consider the cosmic microwave background (CMB). Even if the baryon-to-photon ratio were a thousand times larger or smaller, making the CMB much weaker, we’d likely still be aware of its existence and its relationship to this ratio. However, the actual ratio appears to be set at a value that makes the CMB an exceptionally useful tool for cosmology, which is far more surprising and suggestive of fine-tuning.
• Unknown Discoverability Effects: Critics might argue that varying physical constants could have unknown effects on discoverability. Robin concedes this but notes that the observed fine-tuning is still surprising under naturalism.
• Unknown Anthropic Range Objection: Some might argue that the anthropic range of parameters could be narrower than we think, potentially nullifying the fine-tuning argument for discovery. Robin addresses this by pointing out that even if the anthropic range overlaps with the discoverability-optimality range, the coincidence would still be unlikely under naturalism.

There are advantages over the anthropic fine-tuning argument:

1. Not vulnerable to the multiverse objection.
2. Avoids the “problem of old evidence” in Bayesian confirmation theory.
3. Makes falsifiable predictions (in fact, several times Robin thought he had falsified his argument but later found he had made a mistake in the calculations).
4. For some parameters, avoids difficulties in defining the relevant comparison range of possible values.

Robin goes beyond merely arguing for fine-tuning or design. He says that his argument confirms theism over naturalism. He structures his argument for theism in probabilistic terms. Let E be the claim that the fundamental parameters fall into their DDORs. He argues that:

1. P(E | ~T) << 1, where ~T is the denial of teleology (i.e., the universe is not designed).
2. P(E | theism) is not very small, because we would expect God to create a discoverable universe.
3. Therefore, by the likelihood principle, E confirms theism over its denial.

To support the claim that God would create a discoverable universe (premise 2), Robin argues for the value of science beyond its technological applications:

• It affirms the importance of reason and provides evidence for God’s existence.
• It gives humans confidence in the power of reason, countering skepticism and superstition.
• It allows humans to express the image of God through collective knowledge-seeking.
• It enables appreciation of the glory and ingenuity of God’s creation.
• At its best, it exemplifies ideals of community and individuality.
• It inspires a sense of elegance and transcendence.

Robin suggests it should be seen as a complement to, not a replacement for, the standard anthropic fine-tuning argument.

In Comparison with The Privileged Planet

How does Robin’s fine-tuning for discoverability (FTD) argument compare with the Privileged Planet (TPP) argument? FTD builds a cumulative case from multiple quantified examples where the DDOR range is narrower than the anthropic range and the fundamental parameters optimize discovery. In each case, Robin begins with an aspect of reality important to science and then drills down to the fundamental physical parameters to determine how it depends on them. From this, he calculates the DDOR range. While Robin begins with empirical aspects of nature, his approach is heavy on theoretical physics.

The TPP argument, in contrast, is heavy on the empirical data and light on theory. We do not attempt to relate most of the cases to the fundamental parameters. Instead, we look at how the conditions for complex life correlate with the conditions for scientific observation and discovery. In our case, we tend to apply theory when we extrapolate our Earthly conditions to conditions in other places and times.

The FTD and TPP arguments also differ in their conclusions. The TPP conclusion is modest — the universe is designed for discovery. Robin extends his FTD argument to compare theism with naturalism, and he argues that theism is the better explanation. There is nothing about his comparison of naturalism to theism that would not also apply to our argument. And we would also conclude that the TPP argument confirms theism over naturalism.

FTD captures an aspect of nature that we had not considered in the TPP, namely that the DDOR range is narrower than the anthropic range. Adding that discovery to the TPP argument only strengthens it. 

More recently, Robin has taken the FTD argument up one notch (see the YouTube video above). It is not just that the physical parameters are fine-tuned for discovery, but that we have discovered that they are fine-tuned for discovery. This “discoverability of the fine-tuning for discovery” is the kind of “signal” that a creator could use to communicate with his creation. This is also in line with our conclusions in TPP.