Theistic Proofs of God's Existence

8/22/2019 Theistic Proofs of God's Existence

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Theistic Proofs of Gods

Existence and NaturalTheology

Doctrine of God

Marcos Blanco


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Existence The proofs for the existence of God are withinthe discipline known as the philosophy of

religion. They offer arguments for the

existence of God.

It began in ancient Greek philosophythat is,some 2,500 years agoand continues to this

day. In Book X of Platos Laws(fourth centuryBC) there is the first recorded version of what

we now call the cosmological argument for the

existence of God.


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ExistenceAlthough many philosophy of religion scholars

for those who hold that God has revealed

things to human beings natural theology

usually takes on only a secondary and

auxiliary importance, they have played a main

role in the history of classical theology,

together with natural theology and the via

negativa.


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Existence

It is evident in the fact that most ofphilosophers who have offered theistic proofs

have also held to the validity, in at least some

sense, of revealed theology. That is, most

have believed that God could be known in

other ways than through theistic proofs.


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Aquinas Five Ways

First Way:The first and more manifest way isthe argument from motion. It is certain, and

evident to our senses, that in the world some

things are in motion. Now whatever is in motion

is put in motion by another, for nothing can be in

motion except it is in potentiality to that towards

which it is in motion; whereas a thing moves

inasmuch as it is in act. For motion is nothing

else than the reduction of something from

potentiality to actuality. But nothing can be

reduced from potentiality to actuality, except by

something in a state of actuality.


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Aquinas Five Ways

Thus that which is actually hot, as fire, makeswood, which is potentially hot, to be actually hot,

and thereby moves and changes it. Now it is not

possible that the same thing should be at once in

actuality and potentiality in the same respect, butonly in different respects. For what is actually hot

cannot simultaneously be potentially hot; but it is

simultaneously potentially cold. It is therefore

impossible that in the same respect and in thesame way a thing should be both mover and

moved, i.e. that it should move itself. Therefore,

whatever is in motion must be put in motion by

another.


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Aquinas Five Ways

If that by which it is put in motion be itself put inmotion, then this also must needs be put in

motion by another, and that by another again.

But this cannot go on to infinity, because then

there would be no first mover, and,consequently, no other mover; seeing that

subsequent movers move only inasmuch as they

are put in motion by the first mover; as the staff

moves only because it is put in motion by thehand. Therefore it is necessary to arrive at a first

mover, put in motion by no other; and this

everyone understands to be God. (Summa

TheologicaI.2.2)


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Aquinas Five Ways

The Way of Motion:

(a) The ultimate cause of motion exists.

(b) The first mover is the ultimate cause ofmotion.

(c) Therefore, the first mover exists.


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Aquinas Five Ways

Second Way:The second way is from thenature of the efficient cause. In the world of

sense we find there is an order of efficient

causes. There is no case known (neither is it,

indeed, possible) in which a thing is found to bethe efficient cause of itself; for so it would be

prior to itself, which is impossible. Now in

efficient causes it is not possible to go on to

infinity, because in all efficient causes followingin order, the first is the cause of the intermediate

cause, and the intermediate is the cause of the

ultimate cause, whether the intermediate cause

be several, or only one.


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Aquinas Five Ways

Now to take away the cause is to take awaythe effect. Therefore, if there be no first cause

among efficient causes, there will be no

ultimate, nor any intermediate cause. But if in

efficient causes it is possible to go on to

infinity, there will be no first efficient cause,

neither will there be an ultimate effect, nor any

intermediate efficient causes; all of which is

plainly false. Therefore it is necessary to

admit a first efficient cause, to which everyone

gives the name of God. (Summa Theologica

I.2.2)


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Aquinas Five Ways

The Way of Causation:

(a) All things have an immediate or efficientcause.

(b) The efficient causes cannot go back

infinitely.

(c) There must be a first, uncaused cause.


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Aquinas Five Ways

Third Way:The third way is taken from possibility andnecessity, and runs thus. We find in nature things that are

possible to be and not to be, since they are found to be

generated, and to corrupt, and consequently, they are

possible to be and not to be. But it is impossible for these

always to exist, for 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. Now if this were true, even now there would be

nothing in existence, because that which does not exist

only begins to exist by something already existing.

Therefore, if at one time nothing was in existence, it would

have been impossible for anything to have begun to exist;

and thus even now nothing would be in existence---which

is absurd.


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Aquinas Five Ways

Therefore, not all beings are merely possible, butthere 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 innecessary things which have their necessity

caused by another, as has been already proved

in regard to efficient causes. Therefore we

cannot but postulate the existence of somebeing 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. (Summa TheologicaI.2.2)


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Aquinas Five Ways

The Way of Contingency:

(a) It is not necessary for any particular thingto exist, they are, rather, contingent things.

(b) All possible things at one point did notexist.

(c) If all things are merely contingent, then atone time things did not exist.

(d) There must be a necessary essence thatcaused all contingent things to be.


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Aquinas Five Ways

The Way of Contingency:

(a) It is not necessary for any particular thingto exist, they are, rather, contingent things.

(b) All possible things at one point did notexist.

(c) If all things are merely contingent, then atone time things did not exist.

(d) There must be a necessary essence thatcaused all contingent things to be.


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Aquinas Five Ways

Fourth Way:The fourth way is taken from thegradation to be found in things. Among beings there

are some more and some less good, true, noble and

the like. But more and less are predicated of

different things, according as they resemble in theirdifferent ways something which is the maximum, as a

thing is said to be hotter according as it more nearly

resembles that which is hottest; so that there is

something which is truest, something best,something noblest and, consequently, something

which is uttermost being; for those things that are

greatest in truth are greatest in being, as it is written

in Metaph. ii.


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Aquinas Five Ways

Now the maximum in any genus is the cause

of all in that genus; as fire, which is themaximum heat, is the cause of all hot things.

Therefore there must also be something

which is to all beings the cause of their being,

goodness, and every other perfection; and thiswe call God. (Summa TheologicaI.2.2)


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Aquinas Five Ways

The Way of Goodness:

(a) Things have degrees of perfectionlarger or smaller, heavier or lighter, warmer or

colder.

(b) Degrees imply the existence of amaximum of perfection.

(c) This maximum perfection we call God.


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Aquinas Five Ways

Five Way:The fifth way is taken from the governanceof the world. We see that things which lack

intelligence, such as natural bodies, act for an end,

and this is evident from their acting always, or nearly

always, in the same way, so as to obtain the bestresult. Hence it is plain that not fortuitously, but

designedly, do they achieve their end. Now whatever

lacks intelligence cannot move towards an end, unless

it be directed by some being endowed with knowledge

and intelligence; as the arrow is shot to its mark by the

archer. Therefore some intelligent being exists by

whom all natural things are directed to their end; and

this being we call God. (Summa TheologicaI.2.2)


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Aquinas Five Ways

The Way of Design:

(a) Things in this world are ordered toparticular ends.

(b) Even unintelligent things are predisposedto this and not that.

(c) This order inherent in even inanimatethings necessitates an intelligence to direct it.


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The Ontological Argument

The famous ontological argument was first formulated byAnselm of Canterbury in the eleventh century. This

argument for the existence of God has fascinated

philosophers ever since Anselm first stated it.

How can we outline this argument? It is best construed as areductio ad absurdumargument. In a reductio you prove a

given propositionp by showing that its denial, not-p, leads to

(or more strictly, entails) a contradiction or some other kind

of absurdity. Anselm's argument can be seen as an attempt

to deduce an absurdity from the proposition that there is noGod. If we use the term God as an abbreviation for

Anselm's phrase the being than which nothing greater can

be conceived, then the argument seems to go

approximately as follows:


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The Ontological Argument Suppose

(1) God exists in the understanding but not in reality. (reductio assumption)

(2) Existence in reality is greater than existence in the understanding alone. (premise)

(3) God's existence in reality is conceivable. (premise)

(4) If God did exist in reality, then He would be greater than He is. [from (1) and (2)]

(5) It is conceivable that there is a being greater than God is. [(3) and (4)]

(6) It is conceivable that there be a being greater than the being than which nothinggreater can be conceived. [(5) by the definition of God]

But surely (6) is absurd and self-contradictory; how could we conceive of a being

greater than the being than which none greater can be conceived? So we may concludethat

(7) It is false that God exists in the understanding but not in reality.

It follows that if God exists in the understanding, He also exists in reality; but clearlyenough He does exist in the understanding, as even the fool will testify; therefore, He

exists in reality as well.


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The Ontological Argument

For the critique of Kant to this argument, andthe restate of it by Alvin Plantinga, see

http://mind.ucsd.edu/syllabi/02-

03/01w/readings/plantinga.html
http://mind.ucsd.edu/syllabi/02-03/01w/readings/plantinga.htmlhttp://mind.ucsd.edu/syllabi/02-03/01w/readings/plantinga.htmlhttp://mind.ucsd.edu/syllabi/02-03/01w/readings/plantinga.htmlhttp://mind.ucsd.edu/syllabi/02-03/01w/readings/plantinga.htmlhttp://mind.ucsd.edu/syllabi/02-03/01w/readings/plantinga.html


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The Cosmological Argument

The cosmological argument begins with a fact about experience, namely, thatsomething contingent exists. We might sketch out the argument as follows:

(1) A contingent being (a being such that if it exists it could have not-existed orcould cease to) exists.

(2) This contingent being has a cause of or explanation for its existence.

(3) The cause of or explanation for its existence is something other than thecontingent being itself.

(4) What causes or explains the existence of this contingent being must either besolely other contingent beings or include a non-contingent (necessary) being.

(5) Contingent beings alone cannot provide an adequate causal account orexplanation for the existence of a contingent being.

(6) Therefore, what causes or explains the existence of this contingent being mustinclude a non-contingent (necessary) being.

(7) Therefore, a necessary being (a being such that if it exists cannot not-exist)exists.


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The Argument from Religion

The argument from religious experience goessomething like this:

(a) If an entity is experienced, then it mustexist.

(b) God is the sort of being that it is possibleto experience or encounter directly.

(c) People claim to have experienced Goddirectly.

(d) Therefore, God exists.

The Teleological Arg ment


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The Teleological Argument

or Argument from Design

Design arguments are routinely classed as analogical argumentsvarious parallels between human artifacts and certain natural entities

being taken as supporting parallel conclusions concerning operative

causation in each case. The standardly ascribed schema is roughly

thus:

(a) Entity e within nature (or the cosmos, or nature itself) is likespecified human artifact a (e.g., a machine) in relevant respects R.

(b) a has R precisely because it is a product of deliberate design byintelligent human agency.

(c) Like effects typically have like causes (or like explanations, likeexistence requirements, etc.)

(d) Therefore, it is (highly) probable that e has R precisely because ittoo is a product of deliberate design by intelligent, relevantly human-

like agency.


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Humes critique of the

Design Argument In his Dialogues Concerning Natural Religion, Hume first presented a

powerful version of the Design Argument through his character Cleanthes:

Look round the world: contemplate the whole and every part of it: You willfind it to be nothing but one great machine, subdivided into an infinite

number of lesser machines, which again admit of subdivisions, to a degree

beyond what human senses and faculties can trace and explain. All thesevarious machines, and even their most minute parts, are adjusted to each

other with an accuracy, which ravishes into admiration all men, who have

ever contemplated them. The curious adapting of means to ends, throughout

all nature, resembles exactly, though it much exceeds, the productions of

human contrivance; of human designs, thought, wisdom, and intelligence.

Since therefore the effects resemble each other, we are led to infer, by all

the rules of analogy, that the causes also resemble; and that the Author ofNature is somewhat similar to the mind of man; though possessed of much

larger faculties, proportioned to the grandeur of the work, which he has

executed. By this argument a posteriori, and by this argument alone, do we

prove at once the existence of a Deity, and his similarity to human mind and

intelligence.


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Design Argument These are the facts, Cleanthes says. Next comes his

argument from analogy:

Since therefore the effects resemble each other, we

are led to infer, by all the rules of analogy, that thecauses also resemble, and that the Author of nature

is somewhat similar to the mind of man, though

possessed of much larger faculties, proportioned to

the grandeur of the work which he has executed.

Hume presents five counterarguments against thedesign argument through his character Philo. Here

the three more relevant:


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Design Argument 1. What caused the designer of the

universe?If the cause of the universe is the

mind of some sort of intelligent designer,

Hume said, then why cant we ask who or

what caused that mind? What licenses designarguers to stop the regress once they get to

the designer? Doesnt the order exhibited in

minds require explanation as much as the

order that we see in the universe? For all we

can tell from the Design Argument alone, the

designer of the universe might well have had

a maker.


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Design Argument 2. The Design Argument, even if sound, is

not a proof of God: Humes point here was that

even if the Design Argument is an entirely

successful theistic proof, the designer whose

existence will have been proved is far from the

God of theism. For if your view of the designer is

formed simply by the argument itself, there is no

reason to hold that the designer is unique, that

is, that there is but one designer. There is noreason to hold that the designer is infinite or

perfect. There is no reason to hold that the

designer is everlasting or even still exists today.


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Design Argument 3. The existence of evil in the world makes the

Design Argument unable to prove a morally perfect

designer:Similarly, Hume argued that if one practices

pure natural theology and reaches conclusions about the

designer only on the basis of the Design Argument, the

existence of evil and suffering in the world ruins theDesign Argument as an argument for the existence of a

morally good designer. The evidence for design plus the

evil that we see do not together suggest the existence of

an all-powerful and morally good designer. For if the

designer were omnipotent, it would have the power to

create a world devoid of useless and undeserved

suffering; and if it were morally perfect, it would surely

want to create such a world. Why then is there so much

suffering?


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Arguments Against the

Theistic Proofs

For several reasons, theistic proofs are widelycriticized and even denigrated by believers

and unbelievers in God alike. Here are thereasons:

1. Not a proof:Most of the participants in

the debate concede that none of the theisticproofs succeeds in demonstrating the

existence of God.


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Theistic Proofs 2. Unpersuasive:Perhaps for the previous reason, it is

often pointed out that the theistic proofs are

unpersuasive: few people are converted to belief in God

because of one of the theistic proofs. Bertrand Russell,

for example, tells the following story about his days as a

Cambridge undergraduate: I remember the precisemoment, one day in 1894, as I was walking along Trinity

Lane, when I saw in a flash (or thought I saw) that the

ontological argument in valid. I had gone out to buy a tin

of tobacco; on my way back, I suddenly threw it up in the

air, and exclaimed as I caught it: Great Scott, the

ontological argument is sound. Of course, Russells

impression of the soundness of the ontological argument

did not stick, and for the rest of his life was a confirmed

atheist or at least agnostic.


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Theistic Proofs 3. Irrelevant to religious faith and practice:

Theologians, religious people, and some philosophers

play down or even scoff at the proofs as totally irrelevant

to religious faith and practice. Believers do not need the

proofswhy try to demonstrate something you alreadyknow? And the proofs, it is said, are cold, formal, and

philosophical; they do no call for faith or commitment,

nor do they meet the spiritual needs.

4. Just a philosophical God:The God of thetheistic proofs, it is said, is a mere philosophicalabstraction (a necessary being, the Greatest

Conceivable Being, the Prime Mover, etc.) rather than

the living God of the Bible.


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Theistic Proofs 5. The Methodological Objection:Perhaps

the main objection to the theistic proofs is that

they place the understanding of God in the

multiple sources of theological knowledgematrix, which greatly distort the self-revelation

of God testified to in Scripture. The teachings

of Natural Theology dominate in the

interpretation of biblical information aboutGod's being and acts. In the process, biblical

thought is either completely neglected or

distorted.


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Relative Value of the

Theistic Proofs Instead of attempts to convince people that God exists, it is

better to think of these arguments as indications that it is

reasonable to believe in God. Their effect is to show that

religious faith is a genuine option for thinking people, not to

persuade those who are convinced otherwise.

For decades, theologians, most famously, Karl Barth, havebeen contending that Anselms argument was prepared for

those that already have faith in God and simply need to

discover the intelligibility of their belief. Although arguments

along these lines have helped to dispel the longstandingmyth that Anselms proof is pretheological, they do not seem

to fully elaborate what exactly is involved in making faith

intelligible and how Anselms argument facilitates efforts to

do this.


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NATURAL THEOLOGY

Theistic proofs are used in the context of that is callednatural theology. What is natural theology? John

Macquarries definition accurately captures the

consensus: there is a knowledge of God accessible to

all rational beings without recourse to any special orsupposedly supernatural revelation.

Natural theology is the attempt to reach soundconclusions about the existence and nature of God

(among other things) based on human reasoning alone.Natural theology uses such human cognitive faculties as

experience, memory, introspection, deductive reasoning,

inductive reasoning (such as probabilistic and analogical

reasoning), and inference to best explanation.


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NATURAL THEOLOGY

Natural theology is traditionally associatedwith Catholic tradition, and was given official

endorsement by the First Vatican Council,

which affirmed that God, the beginning andend of all things, can be known with certainty

by the natural light of human reason from the

works of creation. Concilium Vaticanum I,

Constitutio dogmatica Dei Filius,chap. 2,De revelatione, available in Enchiridion

Symholorum (Freiburg: Herder. 1965) 588, no.

3004.


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Revealed Theology and

Natural Theology St. Augustine, in describing how he was taught as a

catechumen in the Church, writes:

From this time on, however, I gave my preference to theCatholic faith. I thought it more modest and not in the

least misleading to be told by the Church to believe what

could not be demonstratedwhether that was because a

demonstration existed but could not be understood by all

or whether the matter was not one open to rational

proofYou [God] persuaded me that the defect lay notwith those who believed your books, which you have

established with such great authority amongst almost all

nations, but with those who did not believe them.

ConfessionsVI.7.


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Natural Theology Here Augustine describes being asked to believe certain

things, that is, take them on authority, even though they

could not be demonstrated. The distinction between what

one takes on authority (particularly the authority of Scripture)

and what one accepts on the basis of demonstration runsthroughout the corpus of Augustines writings.These two

ways of holding claims about God correspond roughly with

things one accepts by faith and things that proceed from

understanding or reason. Each of the two ways will produce

a type of theology. The program for inquiring into God on thebasis of faith/text-commitments will be called revealed

theologymany centuries later. Also, the program for

inquiring about God strictly on the basis of understanding or

reason will be called natural theologymany centuries later.


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Natural Theology The distinction between holding something by faith and

holding it by reason, as well as the distinction between

the two types of theology that each way produces, can

be traced through some major figures of the Middle

Ages. Two examples follow.

First, Anicius Manlius Severinus Boethius (480524)presented an elaborate account of Gods existence,

attributes, and providence. Although a Christian,

Boethius brings together in his Consolation ofPhilosophythe best of various ancient philosophical

currents about God. Without any appeal to the authority

of Christian Scripture, Boethius elaborated his account

of God as eternal, provident, good, and so forth.


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Natural Theology Second, Pseudo-Dionysius (late 5th century) also raised the

distinction between knowing things from the authority of Scripture and

knowing them from rational arguments:

Theological tradition has a dual aspect, the ineffable and mysteriouson the one hand, the open and more evident on the other. The one

resorts to symbolism and involves initiation. The other is philosophicand employs the method of demonstration. EpistolaIX (Luibheid,

1987)

Here we have the distinction between the two ways of approachingGod explicitly identified as two aspects of theology. Augustine,

Boethius, and Pseudo-Dionysius (to name but a few) thus make

possible a more refined distinction between two types of aspects to

theology. On the one hand, there is a program of inquiry that aims to

understand what one accepts in faith as divine revelation from above.

On the other hand, there is a program of inquiry that proceeds without

appeal to revelation and aims to obtain some knowledge of God from

below.


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Natural Theology For Aquinas, there are two sorts of truths about

God:

There is a twofold mode of truth in what we

profess about God. Some truths about Godexceed all the ability of human reason. Such is

the truth that God is triune. But there are some

truths which the natural reason also is able to

reach. Such are the truth that God exists, that he

is one, and the like. In fact, such truths about God

have been proved demonstratively by the

philosophers, guided by the light of natural

reason. (Summa Contra GentilesI.3.2)


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Natural Theology

The truths of natural reason are discovered orobtained by using the natural light of reason.The natural light of reason is the capacity for

intelligent thought that all human beings have

just by virtue of being human.


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Natural Theology Theology (in the Thomistic sense), as it later came to be

called, is the program for inquiring by the light of faith

into what one believes by faith to be truths beyond

reason that are revealed by God. Natural theology, as it

later came to be called, is the program for inquiring bythe light of natural reason alone into whatever truths of

natural reason human beings might be able to find about

God. Theology and natural theology differ in what they

inquire into, and in what manner they inquire. What

theology inquires into is what God has revealed himselfto be. What natural theology inquires into is what human

intelligence can figure out about God without using any

of the truths beyond reasonthat is, the truths divinely

revealed.


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Natural Theology Theology proceeds by taking Gods revelation

as a given and using one divinely revealed

truth to account for another divinely revealed

truth (or to give a higher account of truths of

natural reason). Natural theology proceeds bybracketing and setting aside Gods revelation

and seeking to discover, verify, and organize

truths of natural reason about God. Aquinass

distinctions remain the historical source of howmany contemporary theologians and

philosophers characterize the differences of

their respective disciplines.


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General Revelation vs.

Natural Theology General revelation is a revelatory activity performed by

God.

Natural theology is an interpretative activity performed

by human beings.

In general revelation, God uses nature and history toreveal His will to each person with the goal of their

salvation.

In natural theology, however, human beings addressthese same objects, but with the purpose of

interpreting them from their own perspectives to gain

an understanding of God.


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General Revelation vs.

Natural Theology One should not confuse the revelatory act of

God with the hermeneutical act of human

beings. These two activities are different in

agentand nature.

In general revelation, God is the agent and Hiswill the content; His purpose is to lead each

individual to Himself.

In natural theology, human beings are theagents and the contents are theoretical ideas

about God produced by their imagination.

Theistic Proofs of God's Existence

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