Tuesday, April 20, 2010

The Modal Cosmological Argument, one more time...

With the help of Mickey, from A Philosopher's Blather, I've been able to improve one of the modal cosmological arguments I've been working on.

1. Every existing being (thing, entity) is either contingent or necessary.

(1) is true by definition.

2. There is a possible state of affairs in which nothing contingent exists. (Premise)

"State of affairs" refers to the instantiation or non-instantiation of some concrete object or objects. Excluded are abstract objects, like numbers and propositions. There are many apples, for example, but it is possible for there to be no apples.

3. It is necessarily the case that possible states of affairs are possibly caused.

Assume that there is no cause of the non-existence of apples. Even granting this scenario, there is still a possible world in which the non-existence of apples is caused. Applied to the argument, then, there is a possible world in which the non-existence of contingent things is caused.

In fact, we may weaken the premise even further. Instead of being a sufficient explanation, suppose the cause in question is merely a partial explanation, such that:

3*. It is necessarily possible that possible states of affairs are at least partially caused. (Premise)

For instance, oxygen is a partial cause of water. Oxygen alone is not sufficient to cause water, but it is something needed.

4. It is possible for the non-existence of contingent beings to have at least a partial cause. (From 2 and 3)

5. Therefore, a necessary being exists. (From 1, 4 and S5)


Saturday, April 17, 2010

Metaphysics, Essence and Existence

Philosophers in the Aristotelian tradition have arguably offered the best account of metaphysics. What Thomas, Averroes, Maimonides and others, were able to champion much later after Aristotle was the distinction between essence and existence. It was Parmenides who stated that nothing can differ. All must be one, since things either differ by being or non-being. But, to be distinct from being by being is to be non-being, and to be distinct from being by non-being is to be not-distinct at all. Parmenides concluded that all is one.

What Aristotelians were able to accomplish is: 1) a demonstration that things differ; and 2) that Pure Being is needed to ground each essence that isn't identical to its existence.

1. Something exists.

This is undoubtedly true. In order to doubt that I exist, I must first exist in order to doubt it.

2. Something exists only if there is such a thing as existence.

Again, this doesn't need any extensive argumentation. If there is no existence, then nothing can exist.

3. Existence is Pure Being.

Let's first define a couple of terms:

essence: what something is
existence: that something is (its being, actuality, or reality)

For example, what is the difference between a real dollar bill and an imaginary one? The essence of each is the same (a dollar bill has a specific shape, color, smell, etc.), so obviously the difference is that the real dollar bill has existence!

Now, if the essence of a dollar bill is a dollar bill, then the essence of existence must be existence itself. "Pure Being" or "Pure Existence" are the common philosophical terms for existence itself, so premise (3) is true by definition. I have chosen the term "Pure Being" since that is the most used term by metaphysicians, in addition to the fact that this way we may avoid a linguistic redundancy.

4. Therefore, Pure Being exists.

(4) follows from (1)-(3). So, what else can be known about Pure Being? At least five things:

First, Pure Being must have necessary existence. Imagine a state of affairs in which nothing exists. Is such a state of affairs possible? If the state of affairs exists, then something exists. If the state of affairs does not exist, then it's meaningless to talk about a state of affairs in which nothing exists. In short, it is contradictory to posit an existing state of affairs in which nothing exists. Finally, if something exists, then Pure Being exists, as was shown above.

Secondly, Pure Being must be unique. If there were more than one Pure Being, then there would be distinctions between them. However, to be distinct from existence is to be non-existence. Therefore, what is fully existence (Pure Being) must be one and not many.

Third, Pure Being must be omnipresent (all-present). In every existing place, something exists. Yet, something can only exist if it is grounded in Pure Being. Hence, Pure Being exists everywhere.

Fourth, Pure Being is eternal. We have already seen that Pure Being has necessary existence. Now, what exists necessarily cannot at any time fail to exist; otherwise, it would be contingent and not-necessary. Because Pure Being is necessary, it must exist at all times and therefore must be eternal.*

Fifth, Pure Being must be distinct from everything else that exists. Pure Being has an essence that is identical to its existence, since the essence of existence is existence itself. However, every other existing thing has an essence distinct from its existence (a dollar bill does not have necessary existence, but may or may not exist).

What all of this implies is that while things may not differ by existence, they can (and do) differ by essence. Something either exists or it doesn't, but things may differ by what type of things they are.

This is also the basic metaphysical proof of God's existence found in St. Thomas Aquinas' De Ente et Essentia ("On Being and Essence"). It's not entirely original with Thomas, but I think he puts it the best way. So far, this is the easiest summary I've been able to come up with.

You can be sure of at least three things, then: 1) I exist; 2) God exists; and 3) I am not God.**

*Whether Pure Being is timeless or omnitemporal is up for debate.

**Feel free to read "I" in the first-person, rather than in the sense that "Doug Benscoter exists."

Friday, April 2, 2010

A More Accessible Modal Cosmological Argument

1. Something exists.
2. Every existing being is either contingent or necessary.
3. There is a possible state of affairs in which no contingent being exists.
4. It is necessarily the case that possible states of affairs are explicable.
5. Hence, a necessary being is possible.
6. Whatever is possibly necessary exists in all possible worlds.
7. Therefore, a necessary being exists.

(1) and (2) are easily granted. I cannot doubt my own existence without first existing to doubt it. As for (2), something can either exist in at least one (but not all) possible worlds (contingent existence), or else exist in all possible worlds (necessary existence). Existence in no possible worlds would yield that a thing is impossible, and therefore necessarily non-existent.

(3) is highly plausible. If we represent the sum total of all contingent beings as C, and if all the members of C can at some time fail to exist, it's reasonable to infer that C itself may at some time fail to exist. By analogy, if every part of a house can possibly fail to exist, then the house as a whole can also fail to exist.

(4) doesn't entail that every state of affairs must have an explanation in the actual world. Rather, a state of affairs is defined as "explicable" so long as it is explained in at least one possible world W. Yet, the only thing that is left to explain ~C in W would be a necessary being. So, if it is possible that ~C obtains and that ~C has an explanation in some possible world, then a necessary being exists in some possible world, in confirmation of (5).

(6) and (7) are necessary inferences under the S5 axiom of modal logic. If something necessary does not exist in some possible world, then it is not necessary at all, but contingent, which is contradictory.

Maydole argues very similarly, here. The key difference (besides the use of S5 in the argument above) is that Maydole narrows the scope of his argument to the possibility of C not obtaining in the past, whereas the argument above is more general.