The Modal Third Way - Part 1

This entry is the first of a two-part series in which I will summarize and defend Maydole's formulation of the Modal Third Way (MTW). First, some definitions:

temporally contingent - if x possibly fails to exist at time t, x is temporally contingent

temporally necessary - if x exists at all times in world W, x is temporally necessary in W

explicable - explained in at least one possible world

Here is the first part of the proof:

1. Every temporally contingent thing possibly fails to exist at some time.

(1) is true by definition.

2. If all things fail to exist at some time, then it is possible that all things collectively fail to exist at some past time.

We may grant that there was never a time in this world in which there didn't exist at least one temporally contingent thing. However, (2) is much less ambitious. Even the most ardent skeptic will agree that there is a possible world in which nothing existed in the past. (1) actually implies (2).

3. It is necessarily the case that possible truths are explicable.

Many of us (myself included) are already committed to the view that everything that exists has an explanation of its existence. However, some may not be convinced that this is so. Well, lucky for us, we can significantly weaken our principle and still end up with a good argument! Let's say that a brick just pops into existence uncaused and unexplained. To borrow Maydole's expression, it is "well nigh absurd" to assume that there is no possible world in which the brick's existence has an explanation. Such a conclusion would require that we prove a universal negative, and I doubt anyone is up to such a daunting task.

4. It is necessarily the case that something is explicable only if there was never a time when nothing existed.

Imagine that at some point in the past, nothing existed. Would anything exist right now? Surely not, but I'm sure we can find somebody who thinks so. "Out of nothing comes nothing," still seems much more plausible than its negation. What this implies for us is that if nothing existed at some past time, then nothing would exist right now, in which case nothing is currently explicable. But, we already saw in premise (3) that there are explicable things, which means that the contradictory of (4) is false, implying that (4) is true. Something had to have always existed, but no temporally contingent thing meets the qualification of necessity. Therefore, we have a link from these premises to:


5. If there was never a time when nothing existed, then a temporally necessary thing exists.

Hence:

6. Therefore, something temporally necessary exists.
Q.E.D.

More Thoughts On the Finitude of the Past

1. Every attribute of the universe we have observed is finite.

I'm thinking specifically of the limitations that are exemplified by the laws of nature, in particular. Gravity is limited by the force of the expansion of the universe, for example. It's not as if gravity, electromagnetism, and the strong and weak atomic forces are unlimited; one force may be imposed upon the other, in which case one of them is limited. But, whatever is limited is finite (by definition). Hence, the universe's attributes, especially those of the laws of nature, are finite.

2. The universe's past is an attribute of its temporal duration.

Unless, of course, one is an amazingly strong anti-realist, I doubt even the most fervent Naturalist will doubt premise (2). From these two premises, however, it follows that:

3. Therefore, the universe's past is most likely finite.

(3) is the equivalent to the second premise of the Kalam Cosmological Argument (KCA), which states that the universe began to exist. I like the above argument, since it isn't dependent on the changing field of astrophysics. Thankfully, the current scientific evidence confirms the universe's finitude. It is reassuring, however, that we have additional, philosophical arguments that the universe began to exist.

Is Judges 1:19 Inconsistent with God's Omnipotence?

"Omnipotence" doesn't mean that God can do what is logically impossible. The oft-repeated question, "can God make a square-circle?" can be confidently answered by the classical theist with a "no". God's being omnipotent means that He can do all things, but square-circles aren't things, so God's inability to create them has no effect whatsoever on His omnipotence.

This is where Judges 1:19 comes in. It is commonly alleged that this passage is inconsistent with the doctrine of God's omnipotence. Here is the verse:

"The LORD was with the men of Judah. They took possession of the hill country, but they were unable to drive the people from the plains, because they had iron chariots."

Does this verse imply that God is (or was) incapable of overcoming iron chariots? Obviously, such a feat is logically possible for God, so the claim is that God isn't omnipotent according to Judges. However, does this brief interpretation of the text do justice to the author's original intention?

I should point out that, just intuitively, this seems to be an extraordinarily implausible interpretation. Are we really to believe that God, whom Judges says that mountains quake before (Judges 5:5), the One who brought up Israel from the land of Egypt (Judges 6:8) is really inferior to the chariots of men? Presumably this is what the proponent of the argument is suggesting.

Now, we have at least two ways of responding to this, while maintaining that God is omnipotent. First, we could simply say that the Bible is mistaken on this point. "The arguments of natural theology suffice to show that God exists and is all-powerful, even though the Bible is fallible." This kind of response can be modified like this: "Even if this is what the Bible teaches, God still exists and is all-powerful. At the most, this only implies that the Bible is mistaken on this point."

The above reply, in its latter form at any rate, is correct. Moreover, it is a decent polemical response. Nevertheless, being the Biblical Inerrantist that I am, I believe the Bible is correct whilst maintaining that God really is omnipotent. So, how do we reconcile these? As they say in real estate: the three most important terms are location, location, location. Well, for any interpretation of the Bible, the three most important terms are context, context, context.

For starters, let's take a look at the subsequent text, Judges 1:22-36:

Now the house of Joseph attacked Bethel, and the LORD was with them. 23 When they sent men to spy out Bethel (formerly called Luz), 24 the spies saw a man coming out of the city and they said to him, "Show us how to get into the city and we will see that you are treated well." 25 So he showed them, and they put the city to the sword but spared the man and his whole family. 26 He then went to the land of the Hittites, where he built a city and called it Luz, which is its name to this day.

27 But Manasseh did not drive out the people of Beth Shan or Taanach or Dor or Ibleam or Megiddo and their surrounding settlements, for the Canaanites were determined to live in that land. 28 When Israel became strong, they pressed the Canaanites into forced labor but never drove them out completely. 29 Nor did Ephraim drive out the Canaanites living in Gezer, but the Canaanites continued to live there among them. 30 Neither did Zebulun drive out the Canaanites living in Kitron or Nahalol, who remained among them; but they did subject them to forced labor. 31 Nor did Asher drive out those living in Acco or Sidon or Ahlab or Aczib or Helbah or Aphek or Rehob, 32 and because of this the people of Asher lived among the Canaanite inhabitants of the land. 33 Neither did Naphtali drive out those living in Beth Shemesh or Beth Anath; but the Naphtalites too lived among the Canaanite inhabitants of the land, and those living in Beth Shemesh and Beth Anath became forced laborers for them. 34 The Amorites confined the Danites to the hill country, not allowing them to come down into the plain. 35 And the Amorites were determined also to hold out in Mount Heres, Aijalon and Shaalbim, but when the power of the house of Joseph increased, they too were pressed into forced labor. 36 The boundary of the Amorites was from Scorpion Pass to Sela and beyond.

In verse 22, we again find the phrase, "and the LORD was with them," which connects this passage with verse 19 above. Following this, we see that although the Israelite tribes conquered the land to an extent, they did not obey God entirely. The Canaanites and others who were living in the land remained in the land, which God forbade the Israelites from allowing (which is apparent from the text above, as well as Deuteronomy 7:24 and Joshua 9:24, among others).

The implication here is that although God was with them, Israel didn't do what He commanded them to do. As a result, Numbers 33:55-56 was fulfilled:

"'But if you do not drive out the inhabitants of the land, those you allow to remain will become barbs in your eyes and thorns in your sides. They will give you trouble in the land where you will live. 56 And then I will do to you what I plan to do to them.'"

Throughout the book of Judges, the people of Israel are raided, invaded, and conquered by their enemies. Whenever they return to God, God saves them. It was Israel's lack of faith and disobedience that is responsible for their inability to overwhelm the iron chariots of Judges 1:19, rather than some defect in God's power. This, I think, is a plain reading of the text, which allows the Bible to speak for itself.

We can see Judges 1:19 as a parallel to Numbers 14, in which the men of Israel scout the land of Canaan. They see that the men of Canaan are strong and well-armed, and they doubt they can defeat Canaan. God is displeased by this and commands them to go into the wilderness as discipline. The men of Israel regret their lack of faith and, disobeying God yet again, decide to invade Canaan. The invasion is predictably unsuccessful. Why? Because they did not obey God's command. As Matthew Henry so ably summarized three hundred years ago: "The Canaanites had iron chariots; but Israel had God on their side, whose chariots are thousands of angels, Psalm 68:17. Yet they suffered their fears to prevail against their faith." (Emphasis added).

Pointing to Judges 1:19 may provide the skeptic with an additional reason for unbelief, but fortunately for us, their interpretation of the text is left wanting. After all, it is said that they (referring to Israel, not God) were unable to drive the people from the plains.

The TCA Defended Via Induction

The premises of the Thomistic Cosmological Argument (TCA) need not be supported by deduction, even though the syllogism is itself deductive. Consider the following:

1. All men are mortal.
2. Socrates is a man.
3. Therefore, Socrates is mortal.

Obviously, (2) is supported by induction, since we have to observe that there is a man named Socrates. However, we may conclude that (1) is true by universalizing what we generally observe. Even if we were to theoretically come across an immortal man, (3) would still be more likely true than its negation, given the mortality of the vast majority of human beings (men and women) we have observed.

Likewise, we may appeal to purely inductive inferences in our defense of the TCA. We might state the argument like this:

1. Evident to the senses is motion.
2. Everything in motion is moved by another.
3. If there is no First Mover, there is no motion.
4. Therefore, a First Mover exists.

(1) is obviously based on induction. I have spent some time deflecting objections to (2) that are based on quantum mechanics, but I don't think that is even necessary. For, even if there are instances in which a thing is in motion but is not moved by another, still the majority of things in motion we observe actually are moved by another. If we take a look at the motion of the celestial bodies, we realize that each body's gravity affects the others, so it is reasonable to conclude that one body's motion is caused by (re: "moved by") another.

(3) can also be supported by induction. Just as the motion of the gears of a watch are best explained by the cause of motion found in the spring (ontologically first member of the watch), so too can the motion of the celestial bodies be best explained by the cause of motion found in the First Mover. The removal of the spring would result in the removal of motion among the gears; so by analogy, the removal of the First Mover would result in the removal of motion among the celestial bodies.

Given the truth of (1)-(3), we may conclude that (4) is more likely true than its negation; and we may conclude this without having to appeal to deduction. However, we may infer even more than this. Just as the uniformity* of motion found in the gears is reducible to a single spring, so too is the uniformity of motion found in the celestial bodies reducible to a single First Mover. Hence, we have a legitimate starting point for an inductive argument for monotheism. After all, uniformity is best explained by the causation of a single agent than it is by many agents.


*Uniformity refers to 1) patterns of regularity; and 2) the exemplification of a system in which each member affects the others. The gears of a watch fit this description, and more importantly, the celestial bodies match this qualification.

A Cartesian Argument For Mind-Body Dualism

The following argument is logically valid:

1. Whatever is corporeal is dubitable.
2. My own existence is indubitable.
3. Therefore, I am not corporeal.

(1) may be taken at face value and granted, since we need only posit some possible world in which the corporeal things one observes are illusory. (2), of course, is succinctly expressed by Descartes' maxim, "I think, therefore I am" (cogito ergo sum). I cannot doubt my own existence without first existing! However, if something is true of X, but not of Y, then X and Y cannot be identical. Therefore, it necessarily follows that the mind, or self, is distinct from the body. This is not to say that the mind isn't dependent on the body, or that there is no correlation between mind and body, but only that the two really are distinct substances.

If the above line of reasoning is accepted, then the most commonly accepted naturalistic theory of the mind (materialism) must be rejected. Further, the metaphysical Naturalist will have to rethink his or her worldview.

Is the TCA Based on Outdated, Pre-Newtonian Assumptions?

I often hear opponents to Thomas' First Way claim that one of the two central premises of the argument has been falsified by Newton's Laws. This is basically the entire First Way:

1. Evident to the senses is motion.
2. Everything in motion is moved by another.
3. If there is no First Mover, there is no motion.
4. Therefore, a First Mover exists. (1, 3)

I have already dedicated quite some time in support of (3). It is (2) that is alleged to have been shown false. I think such a conclusion vastly misunderstands the nature of Newton's Laws and, perhaps more importantly, what it is that Thomas is actually stating.

Newton's Laws tell us that if something is in motion, it will continue to be in motion so long as it travels in a straight line. Whatever continues this line of motion does not rely on something to keep its motion going. This should already provide sufficient warrant to raise a red flag. For, the motion of the celestial bodies (and earth) are not at all linear, but elliptical. From this it follows that we do not have any defeater for the premise that everything in motion is moved by another.

Moreover, even something that moves in a straight line without another thing moving it can only do so in the absence of a net external force - something like an absolute vacuum. But of course, such a vacuum does not exist. What we often associate with empty space in a vacuum is simply a convenient way to describe any space whose gaseous pressure is less than atmospheric pressure. The vacuum literally is *something*, rather than nothing, so it counts as a net external force. Newton's first law, while very helpful, is really just an approximation to the truth about motion. We still have to have a First Mover.

Imagine a watch that exists from all eternity. Even if there are infinitely-many gears, none of them will move apart from the cause of motion found in the watch's spring. If the spring is removed, then the gears of the watch will cease to move. By analogy, we can imagine the motion of the celestial bodies existing from all eternity. Even if this were so (barring any argument that the world is finite in age), the motion of these bodies is reducible to the motion caused by the First Mover. Without a First Mover, there can be no intermediate movers. Given that there are intermediate movers, it follows that a First Mover exists.

Thomas' First Way, however, leads only to a metaphysically necessary First Mover, and not to a logically necessary one. For, there are possible worlds in which no motion exists at all. Does the First Mover exist in these worlds, as well? One benefit of modalizing these arguments is that they very often get us to see that some entity actually is logically necessary. Consider the Modal First Way:

1. There possibly exists a First Mover. (In some possible world, a First Mover exists).
2. Whatever is possible is either contingent or necessary.
3. Whatever is contingent can be actualized.
4. A First Mover cannot be actualized.
5. Therefore, a First Mover exists necessarily.

It is often difficult for the atheist to decide which premise he/she actually disagrees with, but the argument is logically valid, so given the truth of each of the premises, the conclusion (5) necessarily follows. I actually went through this argument step-by-step in an earlier post.

I find the above proofs to be both rationally compelling and extraordinarily intriguing. What is left now is to deal with the Gap Problem: how do we get from First Mover to God?

The Impossibility of an Infinite Regress - Causal and Temporal

Thomas rejects the possibility of an essentially-ordered infinite regress of causes. This, however, does not entail the impossibility of an eternal (re: infinitely-old) universe. Imagine a watch that has endured infinite time. If there is no spring, then no matter how many gears there are (even infinitely-many), none of them will be able to move. Likewise, if there is no First Mover, then there can be no intermediate movers. But since it is obvious that intermediate movers exist, it follows necessarily that a First Mover exists.

Bonaventure goes further than this. Not only does he reject the possibility of an infinite regress of essentially-ordered causes, but he also maintains that an infinite regress of temporal events is impossible. William Lane Craig and Mark Nowacki summarize Bonaventure's argument like this:

1. The temporal series of events is a collection formed by successive addition.
2. No collection formed by successive addition can be an actual infinite.
3. Therefore, the temporal series of events cannot be an actual infinite.

(1) assumes the common-sense theory of time, the so-called "dynamic theory", which posits each successive moment of time as an addition to the previous moment. Only the present, under this view, is actually real. The past has been actualized, but no longer exists; the future, however, is merely potential.

(2) is fairly easy to grasp once we reflect on the nature of infinity. No matter how long time has elapsed, it is always and indefinitely possible to add another moment before arriving at infinity. "Infinity", in this respect, is really just a limit. Craig considers the future to be potentially infinite, since although it will continue forever, it will always be finite.

Some have objected to (2), saying that an actual infinite can be formed by successive addition if there was never a beginning to the addition. This would be like someone claiming to have counted down from infinity and end in 0, which is quite strange, regardless of whether the objection is accepted or not. In response, Craig asks rhetorically, "why has the present arrived today, and not yesterday, or at any time in the finite past?" This question is especially pertinent, since assuming the universe's past is infinite, the same amount of time has elapsed before AD 1000 as it has before AD 2000. Why, then, did AD 2000 arrive at the time it did, and not before?

Thomas' objection to Bonaventure's argument is that while the past may not be actually infinite, it may be potentially infinite (and therefore, without beginning). The way to understand this is by conceiving of any time at all in the past. Any time you choose will have a finite interval between then and the present, so any moment in the past can be traversed until we arrive at today.

There are two ways of responding to this. First of all, Thomas' objection (with all due respect to the Angelic Doctor) commits a composition fallacy. The fact that each finite moment of the past can be traversed does not imply that the whole infinite set of past events can be traversed. Even if it could, we still have to reconcile this with the AD 1000-2000 paradox). Secondly, and perhaps more to the point, the past cannot be potentially infinite for the simple reason that every moment of the past has been actualized, and nothing actualized is merely potential. Time travels forward, and not backwards. As a result, a moment of the past T1 cannot be preceded by T2 with T2's being added to T1 via successive addition.

It appears to me, then, that both Thomas' argument for a First Mover and Bonaventure's argument for a Creator are both sound. Of course, the causal premises of each proof have to be defended, but one need only appeal to ex nihilo nihil fit (out of nothing comes nothing) to support them.