1. It is self-evident that there is God? (utrum deum esse sit per se notum)

2. Can it be made evident? (utrum sit demonstrabile)

3. Is there a God? (an deus sit)

1. Whatever we are innately aware of is self-evident. That there is a God is something we are innately aware of. Therefore, it seems it self-evident that God exists.

2. If we perceive the truth of a proposition immediately upon understanding its terms, then the proposition is self-evident. Since God is "that than which nothing greater can be signified" and since "existence in thought and fact is greatewr than existence in thought alone," we immediately apprehend that God exists from what we understand from the word God. Therefore, it is self-evident that there is God.

General

But nobody can think the opposite of a self-evident proposition, but the opposite of God exists can be thought, for the fool has said "There is no God." Therefore it is not self-evident that there is a God.

Thomas distinguishes between a proposition's being self- evident in itself (per se nota) and being self-evident to us (per se nota nobis). Some propositions are self-evident to us, since we know the meaning of the terms: a whole is greater than its parts. First principles of demonstration are self-evident to us when their meaning is grasped by everyone. But some propositions have terms which are not understood by all, even though the predicate forms a part of the subject (or is contained in the subject). Now <God exists> is self evident in itself, since the subject and predicate are identical. But we do not nkow the essence of God, so it is not self-evident to us. It must therefore be made evident to us by things which are more evident to us to begin with, namely God's effects.

1. The awareness of God implanted in us by nature is a general and not altogether perspicuous awareness. It is similar to the difference between the awareness that "someone" is approaching and "Jeff is approaching."

2. Some people who hear the word "God" do not understand by it "that than which none greater can be thought." Some have thought that God is a body. And even if people understood "God" to be mean "that than which none greater can be thought" there would still remain the question of whether they understood it to actually exist (whether they understood that the concept had an instantiation).

1. It seems that God's existence cannot be demonstrated, for it is an article of faith, for as Paul says, faith is concerned with what is unseen, what cannot be demonstrated, that is - made evident.

2. Essential to demonstration is definition, but God - as Damascene points out, cannot be defined. Therefore, we cannot make God's existence evident.

3. God's existence could only be made evident by his effects, but since God is an infinite cause and his effects finite, there is an incommensurability between them. Since, effects incommensurate with their cause cannot make their cause evident, the possibility of a logical demonstration of God's existence from his effects is precluded.

General

St. Paul tells us that "the hidden things of God can be clearly understood from the things that he has made." Therefore, it must be possible to demonstrate that God exists.

There are two kinds of demonstration.

(a) One which shows WHY something is, which argues from cause to effect (or from a things essential nature to its properties). Such an argument proves its conclusion by a premise which is the definition of a thing. (demonstratio propter quid)

(b) One which shows THAT something is, which argues from effects to cause and which proves its conclusion by a premise which states the effect of a thing. (demonstratio quia)

When effects of a thing are better known to us than the cause, we must demonstrate the cause from its effects. Since effects are dependent upon their causes, we can provide such a demonstration.

1. The truths which we can know by natural reason (stated by St. Paul) are not to be numbered among the articles of faith, but are presupposed by them. Since there is nothing to stop a person from taking anything on faith which he cannot personally demonstrate, it is permissible to take the existence of God on faith even if it is the sort of proposition which can be demonstrated by human reason.

2. In a demonstration from effects, an "effect" (of some cause) takes the place of the definition of the cause. And when we are proving that something exists, the central link in the proof is not WHAT a thing is, for we must first know THAT it is before we ask WHAT it is. In proving that God exists from his effects, we will derive the names of God from his effects.

3. An effect will give comprehensive knowledge of its cause when it is commensurable with it, but even with such commensurabilty does not exist, we can at least pass from an effect of x to the conclusion that there is an x, though we cannot know comprehensively WHAT x is. Such is the case with God.

1. Five Ways are not necessary for a person to have a rational belief in God.

The person need not himself work such proofs in order to have a rational belief that there is a God, though Thomas MAY think that the rationality of theistic belief in someway depends on the availability of such proofs in one's community (Anthony Kenny's interpretation), though this may depend on what sense one gives to "rationality."

2. Five Ways DO provide material for a project such as apologetics, even if that was not what motivated Thomas himself to develop these proofs.

3. Five Ways ARE part of a scientia theologiae, a science of theology, in which what CAN be known by reason

B. Common Structure of the Five Ways 

1. empirical starting points [certum est]

It the world we find that there is change, an order of efficient causes, contingency, things which are more or less

perfect, and things without cognition work toward an end). These are all supposed to be obvious

2. The existence of what is observed in the first premise (starting point) implies the existence of something else. [omne quod movetur ab alio movetur]

3. Impossibility of an infinite regress [ad infinitum]

4. There is some first term existent

5. All five ways conclude that there is a legitmate name for this first term existent: Deus

===============================================

6. According to Anthony Kenny, each of the proofs commits a common fallacy, the fallacy of quantificational shift.

Examples:

Every boy loves some girl

==========================

There is some particular girl whom every boy loves.

All action leads to an end.

===========================

There is some end to which all action leads.

First Way:

Everything that is moved is moved by something else.

================================================

There is some (particular) thing that moves everything else.

In every change there must be a common element between the terms of the change

================================================

There must be a element common to the terms of every change.

Everything has an efficient cause.

===================================

There is one cause of everything.

Each thing at some time or other is not.

==========================================

At some time or other each thing is not.

Everything has the possibility of corrupting.

==============================================

There is a possibility of everything corrupting.

Any degree of any perfection is measured against a standard

======================================================

There is a standard by which any degree of any perfection is measured.

Every teleological agent is directed by some intelligence.

======================================

There is some intelligence that directs every teleological agent

Response:

Thomas does not infer these conclusions from the premises given alone, but has additional premises (such as impossibility of an infinite regress) to prove the conclusion validly. Thomas has an argument to get him from the first premise in each argument and the conclusion.

A. The Argument from Motion

(P1) Some things are in motion.

(P2) Everything that is moved is moved by something else.

(P3) It is not possible for there to be an infinite series of movers.

=============================================

(C1) Therefore, there is some unmoved mover

=============================================

(C2) Everyone understands this being to be God (deus).

(P1) Clarified: to be in motion is to undergo a change, locomotion (a kind of accidental change). In other terms, following Aristotle, when X is moved there is an actualization of some potentiality, or a reduction of potentiality to act.

1. Aquinas proves (P2):

(P4) Everything that is moved is, as moved, in potency.

(P5) Everything that moves is, as mover, in act.

(P6) Nothing can be in both potency and act with respect to the same motion.

==========================================

Therefore, (P2) Everything which is moved is moved by something else.

2. Aquinas proves (P3):

(P7) If there is an infinite chain of movers, then each member would be an intermediary cause.

(P8) If every mover is an intermediate cause, then there is no principal cause.

(P9) There is no intermediary cause without a principal cause.

=======================================

Therefore, (P3) It is not possible for there to be an infinite series of movers.

In addition to the Five Ways (argument from motion being the First Way), there is in Thomas an argument from the act of existence or existing which leads to the conclusion that there is a God. Bearing in mind that by "explanation" we mean "causal" explanation, the following seems to be the case:

(1) There are things that exist.

(2) An existing thing X is not identical its essence.

(3) The essence of a thing X does not explain X’s existence (since you cannot deduce the existence of a thing from its essence)

(4) The existence of a thing X does not explain X’s existence (since X would already have to exist to provide an explanation of its own existence and that would mean that X preexists itself).

=============================================================

(5) Therefore, the explanation of a thing’s existence must be something external to the thing.

(6) For any existing thing X, there cannot be an infinite series of external causes of X’s existence.

=============================================================

(7) There must be one external cause of existence for every existing thing.

As in the argument from motion, (6) may be arrived at by a reductio ad absurdum: If each cause of X’s existence were itself in need of a cause of its existence, then no cause of A could exist, and A itself could not exist. But A does exist. So there must be a finite chain of causal explanation for the existence of things which terminates with a being whose nature or essence it is to exist, and this everyone understands to be God.

© Michael Sudduth 1996