V.

  Alvin Plantinga
 
 

XIV. Plantinga's Possible Worlds
 
 

Dr. Forrest Baird, Ph.D. Philosophy, University of Southern Illanois

http://www.whitworth.edu/Academic/Department/ReligionPhilosophy/Classes/PH320W_Baird/handout1.htm
 
 

Alvin Plantinga

Plantinga is a leading figure in what is called "analytic philosophy." This type of philosophy represents not so much a particular content as a method of dealing with philosophical problems. The method uses rigorous logical analysis of propositions using a number of rather technical logical concepts.

Like others who use this method, Plantinga's work is difficult to understand without some background in logic. Plantinga uses a system of modal logic that is on the cutting edge and still the topic of much debate. He relies heavily on certain theorems about modal operators that are not universally accepted. Many articles that critique his work are written almost entirely in symbolic logic and so are not accessible to most students.(24) But by first examining some key concepts Plantinga uses, we should be able to make sense of his version of the argument.

 
 

A. Concepts

 1) Possible Worlds
 
 

Baird:

Plantinga begins his discussion of the ontological argument by borrowing seventeenth century philosopher Leibniz' idea of "possible worlds." A possible world is a possible state of affairs. So, for example, there is a possible world in which I am able to execute dazzling slam dunks and a possible world in which I am lucky to make a basket at all. The second of these, but certainly not the first, is actual or "obtains." But both of these worlds are possible. While the first does not obtain, there is nothing that is logically impossible about it. On the other hand, a world in which I play basketball with a round square is not possible. Such a world not only does not obtain, it could not obtain.(25)

Turning to the ontological argument, Plantinga rewrites the argument in terms of possible worlds. Instead of using a premise which says that God's existence is possible, Plantinga says that God exists in a possible world. If God's existence is possible, then there must be a possible world in which God exists. Of course that possible world might not be this world--just as the possible world in which I can slam dunk is not this world. But if God's existence is at least logically possible (i.e., the concept of God's existence is not a concept like "round square"), then there is a possible world in which God exists.
 
 

 
 
 
 
 

 
 

2) Possible Beings
 
 

Baird:

Immediately after stating that there is a possible world in which God exists, Plantinga makes a revision of this statement. To say "There is a possible world in which God exists" is to talk about God as a possible being. Both Malcolm and Hartshorne had assumed that this makes sense: that one can talk about God as a possible being and discuss the qualities of this possible being. Plantinga questioned this assumption.
 
 
 
 

 B. Properties rather than beings

 

 But, Plantinga argues, it does not make sense to speak of merely possible beings, beings that don't in fact exist. We can't say that "X does not exist" leads to the statement "there is an X such that X does not exist." This would be like saying "there is a thing that does not exist." If it does not exist we can't say "there is a thing...." Or, we can't say "there is a thing such that this thing does not exist." Plantinga suggests that we should be talking about properties. Rather than talking about wheather a particular being exists, we should talk about the exemplification of certain properites. Is there an enstance of this property in a possible world. Baird says:

 "Consider the case of the property of being able to execute dazzling slam dunks. In one possible world (the actual world) that property is exemplified by Michael Jordan (and others). In another possible world (the one of my imagination) that property is exemplified by Forrest Baird. In yet another possible world that property is exemplified by some unidentified being. But in all three cases we are talking about the property of being able to execute dazzling dunk shots. We can ask whether or not that property is exemplified in a particular possible world without talking about the being that exemplifies it.

By revising the argument in terms of properties, Plantinga makes the argument immune to Kant's criticisms about existence not being a predicate. The argument is no longer talking about a thing that may or may not have certain predicates--including existence. It is now an argument about certain predicates and whether or not there is an instance of them. Plantinga even disagrees with Malcolm and Hartshorne about necessary existence. Plantinga holds that not only is existence not a predicate, neither is necessary existence":

As Plantinga Says:

"...A being has no properties at all and [therefore] no excellent-making properties in a world in which it does not exist. So existence and necessary existence are not themselves perfections, but necessary conditions of perfection."(28)

"A being must first exist to have any perfections, so existence, of any type, cannot be one of the perfections a being has.(29) "

C. Maximal Greatness

 Rather than thinking of God in terms of a being, "that which none greater than can be concieved," Plantinga thinks in terms of the property of "maximal greatness" or the property of unsurpassible greatness; none other could possess such a quality for there can only be one such manifestation of this property. If two beings were each "the greatest possible being" wich would be greater than the other?
 
 

But Plantinga doesn't talk about a being with this property. Rther, he asks, is the prperty eximplified in any possible world? Maximal greatness, or Maximal excellence would consist of omnisicence, omnipotence and moral perfection, so the question is, is this quality eximplified in any possible world? But this still doesn't mean that this quality is exemplified in our world. In some other possible world the maximal greatness might be petty in our world. But Plantinga argues: "...The greatness of a being in world W [any given possible world] depends not merely upon the qualities it has in W; what it is like in other worlds is also relevant." (in Baird) (32) So greatness is relivant from one world to another. But to have the property of maximal greatness a being would have to be the greatest in all possible worlds.
 
 

 D. The Point of the Argument

1) Plantinga's Modal Version of the Argument

 
 

P1 A thing has maximal greatness if and only if it has maximal excellence in every possible world.

P2 Whatever has maximal excellence is omniscient, omnipotent and morally perfect.

P3 There is a possible world in which the property of possessing maximal greatness is exemplified.

P4 The property of possessing maximal greatness is exemplified in every possible world.

P5 If maximal greatness is exemplified in every world, then it is exemplified in this world.
 
 

 Barid says:

This argument is valid in its logical structure, but is it sound and persuasive? As mentioned above, to be sound means that the premises must be true and to be persuasive means that most persons would accept the truth of the premises. P1 and P2 are both given as definitions of terms. Plantinga stipulates them as the definitions of the terms he is using.(34) They are, quite literally, true by definition. P4 follows from P1 and P3. Given P1 and P3 there must be some individual (let's call that individual "x") that exists and has maximal excellence in every possible world. No matter what possible world we choose to examine, x would have to have maximal greatness in that world since x possesses maximal excellence in every world. P5 makes the rather obvious point that since our actual world is also a possible world, whatever is true of all possible worlds must be true of this possible world. So P1, P2, P4, and P5 are all true: P1 and P2 by definition and P4 and P5 by logical inference. That leaves only P3.

 
 

 Plantinga's conclusion:

"What shall we say of this argument? It is certainly valid; given its premises, the conclusion follows. The only question of interest, it seems to me, is whether its main premise--that maximal greatness is possibly instantiated--is true. I think it is true; hence I think this version of the ontological argument is sound." [In Baird](35)

2. The Possibility of God's Existence

But can he really prove P3? That might require making a whole other proof for a skeptic.However, God's eixstence is certainly possible in some possible world. Like Hartshorne he argues that if God is possible than he is necessary, or there is no sense in speaking of a merely possible necesary being. If God exists than God's existence cannot be a contingent fact. To question this would be like questioning wheather tables are things to put things on. That is what God is, necessary being, and if God is not acutally necessary than he is impossible but cannot be merely possible. God is not like other beings who may or may not exist. If my Parents had met different people and been married to them rather than each other I would not be me, but they might or might not have had any children at all.This might have happened, therefore, I might or might not have come to be. My existence is contingent. But God is not like this, he either must exist or ealse it is impossible that he could exist, but there is no "might or might not" in the equasion.
 
 

If God might exist in some possible world he must exist in all possible worlds.

E. Objections

1) Tooley, revese possible world thinking

Michael Tooley try's to reverse Plantinga's argument by saying that a statement that is not self contradictory is true in some possible world. So to to say "there is no maximally great being"is true in some possible world. The statement "there may be a unicorn" must be true in some possible world because it could be true. But reversing Plantinga's logic, the talk about a maximally great being must apply to all possible worlds and so there cannot be a maximally great being! [this is in Dr. Baird's notes]

Answer: Mark Stasser comes to the resue in arguing that Plantinga could say that "there is an X" could be true in some possible world unless it is contradictory. If X is the maximally great being. In that case X would have to be true in all possible worlds since a maximally great being could not be merely possible. Both Tooley and Plantinga have concepts that are not self contradictory. Strasser argues that the contradiction test alone is not sufficient to determine the case.
 
 

Here is Strasser's test for determining the possible existence in all possible worlds:
 
 

1. A is not internally inconsistent, and,

2. A does not entail that A1 exist in all possible worlds, or,

3. if A's existence does entail the necessary existence of A1, then we must establish independently that A1 exists in all possible worlds.(45)

But I suggest that the answer is much simpler than turning some test. The reversal of an ontological argument, which many have attempted, goes back to he work of J.N. Findly in his classic argument with Hartshorne. Hartshorne convenced Findlay that the argument of reversal always leads to a ready inversion, so the OA is on again. I suggest that the principle of ontology always works toward reversing its oppossite but doesn't work work the other way around. In other words, anytime the OA is reversed it leads back to inversion. But if one reverses Findly or Tooley it does not. This is illustrated as follows:
 
 

If we say "There is no maximally great being" in some possible world, this is not ture obviously if it is true that there can be such a being in some possible world, because if there is than there must be one in all possible words, since that is what Maximal greatness is; necessary being. IF it is possible for God to exist than God must exist! In other words, "there is no maximally great being" is never a true statment. Tooley's argument is not sound. It would be correct to say, "we dont' know that God actually exists, perhaps God is impossible." But if God is not impossible (because not self contradictory) than it makes no sense to apply the possible world's theory to God's existence in some possible world since for God to be possible is to be necessary in all worlds. NO one could say then that "there is no maximal being in some possible world" because that would be like trying to confine God's necessary existence to some possible world. Trying to imposse God's non-existence upon all possible world's through the possibilitiy of it on some possible world is like trying to confine God's existence to just one possible world, it does not make sense.

2) Existence is not a predicate

This is one of the traditional objections that was assumed to have killed off the original OA when Kant siad that existing is not a quality of perfection that can define it's being. So the phrase "that which nothing greater than can be concieved" is not telling us that God actually exists because we do not know that existing is gratness is predicated upon existing. This is discussed on the previous page (unless I decided not to and forogt). But possibility is a predicate of existence. The possible worlds senerio may get around this argument becasue in this case greatness is not predicated upon existence but upon the possibility of existence, and for that it may well be. Why? Because we have added something to the concept. We are being told something different in this case about the situation. We are being told that not only is this quality one of greatness, but it is one of possible greatness, as oppossed to impossible greatness.

XV. Argument from Temporal Begining
 
 

A. Singularity outside of Time
 
 

This quotation is in argument I, Smith says the singualirty is outside time and has no natural oriign
 
 

B. Outside of Time assumed in the Theory
 
 

C. Ocean of eternity
 
 

Imagine the ocean, endless and boundless, and there is nothing in it but a bit of sea foam. This is analogous of Time and eternity. The boundless eternity in which no change is possible because there is no time, but there are bubbles of time. Each bubble is a space/time envelope like the one that contains our universe. That is all the time and all the change there is, the interior of these bubbles.
 
 

D. Eternal Temoporalities
 
 

But each bubble arises within the the expanse of timelessness. The bubbles themselves are eternal because they are actually in eternity. But inside the bubbles is temporality, the universes live and die and cease to produce life. They become deadmatter floating forever in an exapanse of nothing, unless there is some way in which they cease to be. Perhpas they pop like bubbles of sea foam and are not more.
 
 

1) How would time have ever come to be when the temporal horizon is encased within eternity?
 
 

2) Eternity being changeless how could they ever originate and what would distinguish them from timelessness?
 
 

E. Arbitrary necessity.
 
 

To imagine that time just happened, which is logically contraidictory is arbitrary necessity.

XVI. Being Has to Be
 
 

A. Being is the only logical putative state of affairs.
 
 

Let us say that there is a putative state of affairs such that there is no being. This would not merely be the absnese of universe, it would be the absense of any physical laws whatsoever. It would not be merely darkness but pure nothingness, total absolute nothingness. We cannot even imagine this state of affiars. Moreover, if this were the case nothing could then come to be.

1) Being could not emerge in time
 
 

It would absurdly have to come form nothing at all with no prior cause and no principle of causality. Not even potentiality would exist. Being could not emerge in time for time is a thing, it is characteoristic of being. Therefore it could not emerge from nonbeing. Thus being would have to emerge from non-being at a point beyond space/time (of course space too is a think so thus could not be).

2) Being could not emerge beyond time
 
 

Nor could being emerge in eternity for the putative state of affairs, that nothing is, could never change since it is eternal. Thus the whole notion that there could ever be a state of affirs in which true abolute nothingness is all that is is an impossible state of affiars.

B. The fact and nature of Being.

 

1) Being has to be
 
 

There must have been a state of affairs in which something always was. This something has to be eternal since it always was. It cannot be an endless series of events since that would be an infinite causal regress; so this "somthing" has to be had to give rise to temporal being, since it is absurd to think that something could come from nothing. This eternally existing somthing has to be the ultimate origin of everything that is.
 
 

2) Being let's be
 
 

The nature of being is to be, and to bestow being upon the beings. Temproal being has to arrizse out of etenral being, thus being either causes or otherwise allows temporoal being to come to be. Theologian John McQuirrey uses the phrase "being let's be." (see Principles of Chrstian Theology).

Being is thus giving and opening itself up to further the being of new beings.

C. God and being itself.
 
 

Due to these aspects of being, its eternality and its fecund qualities we can think of being as identified with God. Being is bringing to frution the potentiality of temporal being which is inherent in its nature as being.

 
 

But of course this is not a Chrsitian view of God. Perhaps it is a true view, or perhaps there is more to it than that. We must decide this based upon the religious tradition which we choose to follow. But one can move on from the fact that God does exist in some a priori sense to ask about the nature of God and the religious tradition that best fits him.