A Scientific Argument for the Existence of God, by Robin Collins
Introduction
Evidence of Fine-Tuning
Analogy between biosphere on Mars and the Universe
Fine-tunings:
1. Strength of Big Bang could not differ by even 1 part in 1060 without universe
either collapsing back on itself, or expanding too rapidly for stars to form.
2. If Strong Nuclear Force were stronger or weaker by 5%, life would be
impossible.
3. If gravity had been stronger or weaker by one part in 1040, life-sustaining
stars like the sun could not exist.
4. If the neutron were not ~1.001 times the mass of the proton, all protons
would decay into neutrons or all neutrons would decay into protons, and
life would not be possible.
5. If the electromagnetic force were slightly stronger or weaker, life would be
impossible.
So, initial conditions of the universe all seem necessary for life to exist. If the initial
conditions and parameters of physics were a dart board as large as our galaxy, then the
conditions necessary for life would be a small one-foot wide target that our universe
had to hit. That the initial conditions + parameters of physics are set as they are seems
extremely improbable on the basis of chance, thus an intelligent designer seems
necessary.
Question: Assume Fine-Tuning is True: is the need for an intelligent designer a consequence of that
truth?
Atheist answer: no. Atheist Hypothesis: fine-tuning is a brute fact about the universe that needs
no, and/or admits of no explanation.
Two versions of the Atheist Hypothesis:
 Single-universe Hypothesis: ‘there is only one universe, and it is
ultimately an explicable, ‘brute’ fact that the universe exists and is finetuned’.
 Many-universes Hypothesis: “there exists a ‘universe generator’ that
produces a very large or infinite number of universes, with each
universe having a randomly selected set of initial conditions and values
for the parameters of physics. Because this generator produces so many
universes, just by chance it will eventuallyproduce one that is fine-tuned
for intelligent life to occur.”
Two Arguments for Theism Based on Taking Fine-Tuning of the Universe as a Fact
1. Theism is preferable to single-universe atheism
2. Theism is preferable to many-universes atheism
The Core Argument Rigorously Formulated
It presupposes the Prime Principle of Confirmation, which says: “whenever we are
considering two competing hypotheses, H1 and H2, an observation O counts as evidence in favor
of H1 over H2 if O is more probable under H1 than it is under H2.” The degree of confirmation is
proportional to the degree to which O is more probable under one hypothesis than the other.
Illustrating the principle: Robin, his brother, and the Rock Greeting.
Support for the principle: 1) lots of philosophers think this principle can be derived from
the probability calculus, which is a highly-confirmed mathematical rule set that governs probability. 2)
no recognizably good reasoning is known to violate this principle. 3) the principle has wide applicability
and seems to be a fair description of a very general principle that underwrites all scientific reasoning.
One problem for the principle: how do we know that there are only two
possible hypotheses that are correct? If we don’t know that, then seeing that O is more probable on one
than the other doesn’t tell us it is more likely to be true, since to judge it to mean that requires us to
know how many possible hypotheses are in play. This seems to weaken the extent to which evidence O
stands as confirmation (which, after all, concerns the wider question: is the hypothesis true?).
The Core Argument
(i)
The existence of the fine-tuning is not improbable under theism.
(ii)
The existence of the fine-tuning is very improbable under the atheistic single-universe
hypothesis.
(iii)
Conclusion: From p remises (i) and (ii) and the prime principle of confirmation, it follows
that the fine-tuning data provide strong evidence to favor the design hypothesis over
the atheistic single-universe hypothesis.
Support for Premises
Support for Premise (i) God is good, and it is good for intelligent, conscious beings to exist, so it
is not improbable that God would create a world in which such intelligent life exists.
Support for Premise (ii) Fine-tuning seems improbable under the single-universe hypothesis
offered by the atheist, and is supported by analogies like the universe-as-dart board analogy.
Collins acknowledges that many question the legitimacy of the analogical support for Premise (ii)
and says he offers a rigorous justification based on standard principles of probabilistic reasoning.
Collins also acknowledges that many find the fine-tuning argument unsound because ‘the
universe is a unique, unrepeatable event, [and so] we cannot meaningfully assign a probability
to its being fine-tuned.’ He claims to effectively answer this in the same appendix, and by means
of the same principles of probabilistic reasoning.
Some Objections to Core Version
Objection 1: More Fundamental Law Objection
As far as we know, there could be a more fundamental law under which the parameters of
physics must have the values they do. Given that possibility, it is not improbable that the known
parameters of physics fall within the life-permitting range.
Collins’ Reply:
1.
This is “entirely speculative” (Potter rejoinder: no it is not, since the discover of deeper
laws explaining phenomena previously understood only incompletely is common in the
history of science)
2.
Moves the improbability of the fine-tuning up one level, to that of the postulated
physical law itself. (Potter rejoinder: this requires us to treat the laws of nature as
needing explanation….is this plausible in the way that the diverse-yet-finely-tuned
constants and specific parameters, across many different features of natural
phenomena, seem to need explanation?)
Objection 2: Other Forms of Life Objection
As far as we know, other forms of life could exist even if the parameters of physics were
different.
Collins’ Reply: Most cases of fine-tuning used by purveyors of the Core Argument do not make
this presupposition.
Objection 3: Anthropic Principle Objection
Weak Anthropic Principle: if the laws of nature were not fine-tuned, we could not be here to
comment on the fact.
Anthropic Principle Objection: the fine-tuning is not really improbable or surprising at all under
atheism, but simply follows form the fact that we exist.
Collins’ Reply: restate Core Argument in terms of our existence: our existence as embodied,
intelligent beings is extremely unlikely u nder the atheistic single-universe hypothesis, but not
under theism.
Objection 4: The “Who Designed God?” Objection
Postulating the existence of God does not solve the problem of design, but merely transfers it
up one level without answering the question at that level, i.e., “Who Designed God?”
Or, as George Smith puts it: “If the universe is wonderfully designe,d surely God is even more
wonderfully designed. He must, therefore, have had a designer even more wonderful than He is.
If God did not require a designer, then there is no reason why such a relatively less wonderful
thing as the universe needed one.”
Collins’ Replies:
First Reply: atheist claim presupposes something dubious: that the designer of an
artifact must be a complex as the artifact. He concedes that, nonetheless, in our world,
organized complexity is generally produced only by systems that have equal or greater
organized complexity.
Second Reply: At best, the atheist objection only works against a version of the design
argument that claims that all organized complexity needs an explanation. Collins’ version of the
Core Argument “only required that the fine-tuning be more probable under theism than under
atheistic single-universe hypothesis.” This requirement is still met even if God exhibits
tremendous internal complexity far in excess of the universe. (Potter: this amounts to taking
advantage of the fact that the Core Argument does not establish reasons for thinking theism is
true, only for preferring the theistic hypothesis over the atheistic single-universe hypothesis
(where those are the only two hypotheses being considered).
EXAM WILL ONLY COVER THROUGH THE END OF OBJECTION 4…SKIP the sections on the manyuniverses hypothesis