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Does God Exist?

Christianity 101

Martin Ester

January 24, 2013

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Does God Exist?

• Why is the existence of God important?

• The answer to many ultimate questions

depends on that question, e.g.

Why are we here?

What is the purpose of life?

C. S. Lewis

“ God is not the sort of thing one can be

moderately interested in.”

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Does God Exist?

• Possible answers:

Yes: Theism

Don’t know / cannot know:

Agnosticism

No: Atheism

� (Keller 2008), chapters 8 and 9

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What do we Mean by “God”?

A supernatural being

• Omnipotent

• Omniscient

• (Omnibenevolent)

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Arguments For the Existence of God

• The Cosmological Argument

• The Fine-Tuning Argument

• The Moral Argument

�A lot more arguments have been discussed in

the course of the centuries, see e.g.

(Wikipedia 2013).

�These are arguments, no proofs.

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The Cosmological Argument

(Craig 1979)

• Whatever begins to exist has a cause.

• The universe began to exist.

• Therefore, the universe has a cause.

Modus ponens

(A�B) and A

implies B

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The Cosmological Argument

• Whatever begins to exist has a cause.

Is the basis of the natural and social sciences.

Why did the bone break?

What caused the financial crisis?

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The Cosmological Argument

• The universe began to exist.

• Big Bang theory (Wollack 2010) is the prevailing

cosmological model that explains the early

development of the Universe.

• The Universe was once in an extremely hot and

dense state (singularity) which has expanded

rapidly since then.

• The Big Bang occurred approximately 14 billion

years ago.

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The Cosmological Argument

• What can we say about this cause?

• Must be uncaused.

• Must be changeless, timeless, immaterial.

� God

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The Fine-Tuning Argument

• The laws of physics have fifteen constants that

need to be tuned very accurately to the actually

observed values to allow life in our universe.

(Collins 2006)

• The rate of expansion of the universe depends

on its total mass and energy as well as the

gravitational constant.

• The gravitational constant G is a parameter

involved in the calculation of gravitational force

between two bodies.

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The Fine-Tuning Argument

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• If the rate of expansion had been smaller by

, then the universe would have collapsed

again.

• If that rate had been greater by then stars

and planets could not have formed.

610

1

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The Fine-Tuning Argument

• The strong nuclear force is the

force between two or more

nucleons, which is responsible

for binding of protons and

neutrons into atomic nuclei.

• If the strong nuclear force had been slightly

weaker, then only hydrogen could have formed.

• If that force were slightly stronger, all hydrogen

would have been converted to helium, and the

fusion furnaces of stars would not exist.

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The Fine-Tuning Argument

• The observed combination of the fifteen

physical constants is extremely unlikely to

happen by chance.

• The “multiverse” hypothesis claims that there

is a very large number of universes with

different values of the physical constants.

• This hypothesis makes the existence of one

universe supporting life much more likely.

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The Fine-Tuning Argument

• But the “multiverse” hypothesis postulates a

very complex model.

• Scientists prefer simple models over complex

models, that tend to overfit to the observed

data and not generalize well to unobserved

data.

� Occam’s Razor

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The Fine-Tuning Argument

• The assumption of a Creator God can explain

the observed physical constants necessary for

life within a single universe.

• Stephen Hawking (Hawking 1988)

“It would be very difficult to explain why the

universe should have begun in just this way,

except as the act of a God who intended to

create beings like us.”

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The Moral Argument

• Many people say “No one should impose their

moral views on others”.

• Moral relativism: moral views are relative to

cultures and individuals.

• But most people believe in the

existence of “human rights”,

absolute moral standards,

e.g. that nobody should be

killed.

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The Moral Argument

• “Moral … is an orientation toward under-

standings about what is right and wrong, just

and unjust, that are not established by our

own desires or preferences but are believed

to exist apart from them.” (Smith 2003)

• Why do moral standards exist?

- Created by humans/society

- Result of evolution

- God-given

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The Moral Argument

• Created by humans/society

• “Honoring individual dignity means that in the

long run everybody is better off.”

• What if the majority decides not to give human

rights to the minority?

�Nazis and Jews

• The Nazis had the majority, but today we

nevertheless “know” that the Nazis were

wrong.

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The Moral Argument

• Result of evolution (Rutherford 2007)

• Altruism: selfless giving of oneself to others

with no expectation of receiving anything in

return.

• Altruistic individuals may suffer loss, injury or

death.

• Such behavior does not provide a selective

advantage.

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The Moral Argument

• A community with altruistic individuals can still

have a selective advantage.

• But genes are inherited by individuals, and

selection operates at the level of individuals,

not populations.

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The Moral Argument

• God-given

• If there is a cause of the Universe, a creator

who fine-tuned it, then it is plausible that he

has given all humans the same moral standards.

• C.S. Lewis (Lewis 1952)“If there was a controlling power outside the universe, it could

not show itself to us as one of the facts inside the universe …

The only way in which we could expect it to show itself would

be inside ourselves as an influence or a command trying to get

us to behave in a certain way. And that is just what we do find

inside ourselves.”

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Conclusion

• There is no proof for the existence (or non-

existence) of God.

• There are good arguments for the existence of

God.

• The existence of God provides a “unifying”,

compelling explanation of the cause of the

universe, the fine tuning of its physical

constants, and the existence of absolute moral

laws.

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References

Francis Collins: “The Language of God”, Free Press, 2006.

William Lane Craig: “The Kalam Cosmological Argument”, Library of philosophy

and religion, Macmillan, 1979.

Stephen Hawking: “A Brief History of Time”, Bantam Books, 1988.

Tim Keller: “The Reason for God”, Penguin Books, 2008, chapters 8 and 9.

CS Lewis: “Mere Christianity”, Barbour and Company, 1952.

Matthew Rutherford: “The Evolution of Morality”, University of Glasgow, 2007.

Christian Smith: “Moral Believing Animals: Human Personhood and Culture”,

Oxford University Press, 2003, page 8.

Wikipedia: “Existence of God”, http://en.wikipedia.org/wiki/Existence_of_God,

retrieved on January 19, 2013.

Edward J. Wollack: Cosmology: The Study of the Universe, Universe 101: Big

Bang Theory, NASA, 2010.