A Scientific Argument for the
Existence of God
by Robin Collins
Collins’ Analogy
If we discovered a functioning Biosphere on
Mars, would we assume it was created by
chance, or rather, by some intelligent
designer(s)?
Evidence of Fine-Tuning of the Universe
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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.
If Strong Nuclear Force were stronger or
weaker by 5%, life would be impossible.
If gravity had been stronger or weaker by
one part in 1040, life-sustaining stars like
the sun could not exist.
Fine-tuning Evidence (cont’d)
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•
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.
If the electromagnetic force were slightly
stronger or weaker, life would be
impossible.
Collins’ Dart Board Analogy
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.
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 fine-tuned’.
• 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 eventually
produce 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
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•
Theism is preferable to single-universe
atheism
Theism is preferable to many-universes
atheism
The Core Argument Rigorously Formulated
• The Core Argument presupposes the
Prime Principle of Confirmation, which
says: “whenever we are considering two
competing hypotheses, H1 and H2, an
The Core Argument Rigorously Formulated
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.
Considering the Prime Principle of Confirmation
• Illustrating the principle: Robin, his brother, and
the Rock Greeting.
• Formal support for the principle: 1) lots of
philosophers think this principle can be derived
from the probability calculus, which is a highlyconfirmed 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 Problematic Way of Taking the Principle
• If we think that applications of the principle reveals
which hypothesis is more likely to be true, there is a
problem:
• 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-asdart 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
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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)
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-finelytuned 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, yet the Core
Argument assumes forms of intelligent life
must be like us.
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:
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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.
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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).
NOTE: we are skipping the many-universes hypothesis sections.