Dr. Richard Spencer

June, 2015

True and Reasonable Faith Theistic Proofs

Second Session

Outline • Epistemology

– How do we decide what is true?

– Faith and reason

• Rationality; belief, knowledge and warrant

– When does belief become knowledge?

– Is belief in Christianity reasonable?

• What is the foundation of proper Christian faith?

• What good are theistic “proofs”?

• Classic Theistic Proofs

• Other Theistic Proofs

• Modern evidence for the Christian worldview

• Apologetics

Review – What is wrong?

−20 = −20 16 − 36 = 25 − 45

42 − 4 × 9 = 52 − 5 × 9

42 − 4 × 9 +81

4= 52 − 5 × 9 +

81

4

42 − 2 × 4 ×9

2+

9

2

2

= 52 − 2 × 5 ×9

2+

9

2

2

4 −9

2

2

= 5 −9

2

2

4 −9

2= 5 −

9

2

4 = 5 0 = 1

Review

• We covered a lot of material quickly, but I want all of us to know:

– Faith and Reason work together in every worldview; Van Til emphasizes that the main difference between Christians and others is their ultimate standard. Ours is God’s Word (i.e., authority), theirs is autonomous human reason.

– We use our reason in service, not as the final judge, but nothing about Christianity is unreasonable!

– For a belief to be reasonably called knowledge, there must be warrant. The inner witness of the Holy Spirit is great warrant!

– Proof, in any formal sense, cannot be required for a belief to be considered knowledge.

Review

• We discussed four essential principles of knowledge:

– The law of noncontradiction

– The law of causality

– The basic (but not infallible) reliability of sense perception

– The analogical use of language (we are made in God’s image and can think his thoughts after him, but ours aren’t identical)

• The Bible, and therefore God, universally assumes these four principles, we are not imposing them from outside

• Now let’s move on to consider the classic theistic proofs

Classic Theistic Proofs

• As we examine these, we must remember that they can be useful to us as Christians, but if someone is committed to human reason as the ultimate judge, these proofs cannot lead to the true God of the Bible; they can only lead to deism and a god made after man’s image; one who will let you sin and not hold you accountable

• Therefore, these proofs can be used to support a Christian worldview, but in apologetics we must always present the gospel first and emphasize that the Bible is the standard; God commands everyone everywhere to repent and believe (to stop suppressing the truth)

Anselm: Ontological Argument (a priori) • Ontology is the study of being, or existence

• Anselm (1033-1109) was the Archbishop of Canterbury

• He wanted a proof not only of God’s existence, but also that he has the superlative attributes of the biblical God

• He reasoned:

– God is the greatest conceivable being

– It is greater to exist in reality than merely in the mind

– Therefore, God exists

• This was originally expressed differently, the rather famous phrase is that God is “that than which no greater can be conceived”

• Great reference: http://plato.stanford.edu/entries/ontological-arguments/

Thomas Aquinas

• Thomas Aquinas gave five proofs for the existence of God in his Summa Theologica

1. Unmoved mover

2. First cause

3. Necessary being

These first three are all forms of the Cosmological Argument (i.e., because the cosmos exists, there must be a cause) and are based on the impossibility of an actual infinity of causes

4. Degrees of goodness (The Moral Argument)

5. Teleological (having to do with the purpose, or end of creation)

1. Unmoved Mover

• Aquinas argued:

“It is certain, and evident to our senses, that in this world some things are in motion. Now whatever is in motion is put in motion by another… If that by which it is moved be itself moved, then this also must be moved by another … But this cannot go on to infinity … Therefore, it is necessary to arrive at a first mover which is moved by no other. And this everyone understands to be God.”

– By “motion”, Aquinas did not just mean a change in position, but any change in state

– He is not just considering a temporal sequence, but also simultaneous events (like gears moving together)

1. Unmoved Mover - Illustration

• Let’s watch a short video (10X real speed)

• What can you conclude?

1. Unmoved Mover - Illustration

• Something happened first!

2. First Cause

• Aquinas argued:

“In the world of sense we find there is an order of efficient causes. There is no case known (nor indeed, is it possible) in which a thing is found to be the efficient cause of itself … Now in efficient causes it is not possible to go on to infinity … Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.”

– We need to know about Aristotle’s causes. Think about a marble statue:

The material cause is the marble The formal cause is the design The final cause is the purpose The efficient cause is the sculptor The instrumental cause is the chisel

3. Necessary Being

• Aquinas argued:

“We find in nature things that are possible to be and not to be … that which is possible not to be at some time is not. Therefore, if everything is possible not to be, then at one time there could have been nothing in existence [and] even now there would be nothing … Therefore, not all beings are merely possible, but there must exist something the existence of which is necessary. But every necessary thing either has its necessity caused by another, or not. Now it is impossible to go on to infinity in necessary things … Therefore we must admit the existence of some being having of itself its own necessity and not receiving it from another, but rather causing in others their necessity. This all men speak of as God.”

Thomas Aquinas

• Thomas Aquinas gave five proofs for the existence of God in his Summa Theologica

1. Unmoved mover

2. First cause

3. Necessary being

These first three are all forms of the Cosmological Argument (i.e., because the cosmos exists, there must be a cause) and are based on the impossibility of an actual infinity of causes

4. Degrees of goodness (The Moral Argument)

5. Teleological (having to do with the purpose, or end of creation)

Thinking about Infinity

• We can honor God, and appreciate him more, by meditating on any aspect of his creation, including mathematics!

• All three of these proofs talk about the impossibility of an infinite sequence of causes

• Obviously, in some sense, we correctly speak about God being “infinite”

– He exists without physical boundaries and outside of the constraint of time

– His perfections are all beyond measure and are, in fact, normative (e.g., his holiness, justice, goodness, truth)

• But, what about the physical universe?

Why is an Actual Infinity Impossible?

• There are different kinds of infinity, for example; – The natural numbers are “countably infinite”

– The real numbers are “uncountably infinite”

– In set theory there are other types of infinity as well

• A “potential” infinity is possible; this refers to the idea that you can, for example, add 1 to any natural number and get a new number, the total number of natural numbers you obtain will grow without bound, it is a potential infinity

• An “actual” infinity is not possible; this refers to a collection of things that actually is infinite in number (not just growing without bound, not just able to keep growing forever)

• The impossibility of an actual infinity is proven by looking at the logical contradictions that arise if one does exist, for example, Hilbert’s Hotel (named after David Hilbert)

Hilbert’s Hotel

• Suppose I have a hotel with an actual infinite number of rooms and they are all occupied, then

– If you come and ask for a room, I can say “No problem” and simply move the person in Room 1 to Room 2, the person in Room 2 to Room 3 and so on until I have Room 1 open for you! The total number of guests remains the same; infinite.

Hilbert’s Hotel

• Suppose I have a hotel with an actual infinite number of rooms and they are all occupied, then

– In fact, I can accommodate an infinite number of new guests. For example, I can move the person in Room 1 to Room 2, the person in Room 2 to Room 4, the person in Room 3 to Room 6, and so on, doubling every room number. So now all of the odd rooms are open and I can accept all the new guests. Again, the total number of guests won’t change!

Hilbert’s Hotel

• Suppose I have a hotel with an actual infinite number of rooms and they are all occupied, then

– I can also have an infinite number of guests check out and I will still be full; for example, if everyone in an even room checks out, I can just move the remaining guests into sequential rooms starting with Room 1 and I will still have an infinite number of guests and all of my rooms will be full.

Hilbert’s Hotel

• Suppose I have a hotel with an actual infinite number of rooms and they are all occupied, then

– But, if all the guests with room numbers greater than 3 check out, I will be back down to a finite number of guests (3)!

• This is all obviously absurd, which is why an actual infinity cannot exist

• Now let’s examine a modern expression of the cosmological argument

Basic Cosmological Argument

• William Lane Craig expresses the kalaam Cosmological Argument as a syllogism:

1. Whatever begins to exist has a cause

2. The universe began to exist

3. Therefore, the universe has a cause

• The logic in this syllogism is correct; therefore, if the two premises are true, the conclusion is guaranteed to be true

• Let’s examine each of the premises

Premise 1: Whatever begins to exist has a cause

• Believe it or not, this is disputed by some!

– The atheist Quintin Smith said, “the most reasonable belief is that we came from nothing, by nothing, and for nothing.”

But if someone wants to digress into irrationality, then no argument is possible!

– Stephen Hawking & Leonard Mlodinow, in their book The Grand Design wrote that “Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist.” (pg 180)

There is a sleight of hand going on in this statement. It says “spontaneous creation is the reason there is something rather than nothing”, but this “creation” doesn’t come from nothing!

Premise 1: Whatever begins to exist has a cause

• Hawking does not really mean that something comes from nothing; there must be a “quantum vacuum” in which the laws of physics are operative, but where did that come from?

• In the “multiverse” idea proposed by Hawking and others you still have two serious problems:

– The quantum vacuum is not nothing, so it must either be created or eternal, but if it is eternal why do the laws of physics include the 2nd law of thermodynamics?

– An actual infinite number of universes is impossible; infinity is the atheist’s “God of the gaps” as we will see again & again

Second Law of Thermodynamics

• Why is it that physical processes don’t run backwards?

• For example, a burning log produces smoke, ash and heat, but you never see these things recombining to form a new log!

• In any thermally isolated system, the disorder cannot decrease (disorder is measured by entropy); this is the 2nd law of thermodynamics

• One result of the second law is that the entire universe will eventually run down; it will be transformed into a totally disorganized distribution of energy and mass without form, function or life

Conclusion

• We conclude, therefore, that premise 1 is true:

– Whatever begins to exist has a cause

• Now let’s move on to consider premise 2

Premise 2: The universe began to exist

• Craig offers two ways of supporting this premise

– Philosophical: Since an actual infinity cannot exist, the universe cannot be eternal because its history would contain an infinite sequence of events

– Scientific: There are two lines of argument

• The universe is not eternal, but started with the Big Bang (if you don’t agree with the Big Bang that’s fine, if you agree there was a beginning you already agree with the premise and you can use the Big Bang to argue with others)

• The 2nd-law of thermodynamics guarantees that if the universe is eternal, it would already have experienced heat death and we wouldn’t be here to speculate about its eternality

The Universe Began to Exist

• Other possible theories

– Static; this model is not reasonable because:

• The universe would need to be infinite and perfectly balanced or gravity would cause it to collapse; in fact, a static universe has been proven to be unstable

• If the universe were static and infinitely old, no stars would still be burning and it would already have experienced heat death

• If the universe were static the sky would be infinitely bright (assuming a roughly uniform density of stars)

• If the universe were static there would be equal numbers of stars of all ages (assuming they were somehow continually being created and dying), but this is not what we observe (they are all relatively young)

The Universe Began to Exist

• Other possible theories

– Bouncing; this model is not reasonable because:

• The data now point to an increasing rate of expansion of the universe, which means that it will never collapse

• There is no known mechanism to cause the bounce – a big crunch would most likely result in the end

• Even if it did somehow bounce, it isn’t clear what would happen with the total entropy

– Entropy is a measure of the disorder in a system

– The 2nd law of thermodynamics says that entropy will never decrease for a closed system

– If entropy never decreases, the universe would eventually stop bouncing and die