On rereading my discussion of Stephen Hawking’s The Grand Design, I realize that not only did I not explain why “string theory” doesn’t address the problem of contingency, I didn’t even adequately define contingency, or why it constitutes a problem for atheists. As it is, the conclusion appears to be a two-part exercise in begging an inarticulate question.
So let me make amends by supplying the deficiency:
Contingent, and its antonym necessary, are philosophical terms referring to a particular ontological condition. Given the existence of a being, is its existence conditional or absolute? Is there a time or condition in which the being did, will or could not exist? Does it depend on certain things being just so, on certain causes producing particular results? If so, its being is contingent. Now, a contingent being may be a required condition to the existence of other beings; it can also be an inevitable product of other conditions. But as long as its own existence is conditioned by the existence of other beings, as long as it can have not existed or has the potential to no longer exist, it cannot be said to be necessary.
I must point out here that, because a contingent being’s existence is conditional, it doesn’t follow that the being’s existence isn’t real. Knowing that a brick wall’s existence is conditioned by the existence and action of a brick factory, a cement mixer and at least one mason won’t save you if you slam your Prius into it at eighty-five miles an hour; hopefully (though not probably) the equally contingent airbag and seatbelt will.
Keep in mind also that the description of a being as contingent grants its existence causa argumenti, even in the case of beings of reason. A being of reason may be real, or it may be preter-real; that is, its reality may or may not be conditioned by materiality or physicality. However, its contingency is not conditioned by its existence; a being of reason doesn’t become contingent simply because its existence hasn’t been verified empirically.
The contingency problem was introduced by St. Thomas Aquinas in Summa contra gentiles (not in Summa theologica, as is commonly thought, where it’s presented within a summary of his five arguments for the existence of God). Put simply, nothing we observe within the universe fulfills the absolute condition of necessity. This suggests that the existence of the universe itself is conditional. Now, if only a portion—even a massive portion, like 99.99999999+%—of the beings comprised by the universe existed conditionally, this argument would be a composition fallacy. However, the absence of even one necessary being among the near-infinite beings makes the argument persuasive, if not conclusive.
Given the conditioned existence of the universe, the absence of a necessary being creates a situation where beings continually have to pop into existence in order to explain the existence of other beings in an infinite regress. An infinite regress is “an attempt to solve a problem which re-introduce[s] the same problem in the proposed solution. If one continues along the same lines, the initial problem will recur infinitely and will never be solved.” Solving each individual question, “Where did X come from?” would never solve the ultimate question, “Where did the universe come from?”
To stop the regress, St. Thomas argued that there must be one Necessary Being, one Being whose “be-ing” is absolute, upon which all contingent beings depended either directly or indirectly for their own existence. By definition, such a Necessary Being can’t be regressed because its existence neither needs nor admits of a source. It can’t not be: answering the question “Where did It come from” with “It just is” isn’t a refusal to answer, but rather the only answer possible. This Being, he concluded, is God, who in His declaration to Moses expressed the fundamental quality of His Being as be-ing: “I AM WHO AM” (Ex 3:14). [Actually, St. Thomas' exact words are, "This all men speak of as God", acknowledging that people can come to this conclusion without knowing anything of Judaism or Christianity.—TL]
For many years, the atheist response was the so-called “steady-state universe”. To solve the regress problem, they argued that matter fulfilled the criteria of absolute existence: as long as matter always is, then the individual matter composites comprised by the universe can all be contingent without requiring the existence of a God to explain the whole shebang. So when Georges Lemaitre introduced the “Big Bang” theory to explain certain red shifts observed in the motions of stars, skeptics immediately took note of his Catholic priesthood and complained that he was simply trying to put a Creator back into the picture they’d pushed Him out of.
The discovery of background radiation in the spot predicted by Fr./Dr. Lemaitre spelled the end of the steady-state universe. In effect, the infinitesimally small, infinitesimally heavy source singularity represents an impenetrable wall, before which neither mass nor the fundamental constants of the universe could be said with any empirically justified confidence to have existed. The contingency of the universe, to atheists’ dismay, could no longer be ruled out.
To be fair, theories presented since then to provide natural sources for the universe can’t be characterized as desperate attempts to repair the atheist position. Not only is such a treatment uncharitable and untrue, it’s also the logical fallacy the soon-to-be-Blessed John Henry Cardinal Newman described as “poisoning the well”. The way that St. Thomas formulated the Argument from Necessity, the Necessary Being solution obtains even if natural conditions are such that there’s an infinite cycle of contingent beings bringing forth other contingent beings. Matter may have existed from all time, and may continue to exist into infinity; it doesn’t follow from that postulation that matter isn’t contingent. What we don’t know—and what science may never be equipped to find out—is whether it’s possible for matter to have not existed; right now, the statement that matter can be neither created nor destroyed is an article of faith rather than a reasoned deduction from the evidence. So long as that question remains unanswered, Ockham’s Razor can’t excise a Necessary Being, nor can the theist explanation be dismissed by the “god of the gaps” straw man. [Recent experiments which isolated antimatter also proved that matter and antimatter annihilate each other when they come in contact with each other. If they can be destroyed, then matter can't fulfill the definition of "absolute".—TL]
General relativity poses a chicken-and-egg regression which the invocation of string theory fails to solve. For if gravity is a function of mass, then how can gravity impose mass on matter? But if gravity gives mass to matter, then how can gravity be a function of mass? Therefore, gravity/mass must be a function of matter, not independent of it. But if that’s so, then gravity can’t pre-exist matter in order to create it ex nihilo. As a result, string theory doesn’t overcome the problem of contingency.
Hawking’s solution depends, then, on making gravity essential rather than accidental. Essence is the principle, if you will, that makes the being what it is: its beingness. Accidence is a quality of the being that makes it distinct from beings in the same set: the peculiarities that make this chair different from that chair. Accidents are preter-real; they can be said to be real only so far as they inhere in real beings, but have no being themselves. Accidents, then, are contingent by definition. Making gravity a being only sends the argument off to chase its own tail: it solves nothing.
Hawking’s ontological errors are common within the scientific community, among whom are a great number of nontheists. They’re often educated in the history of science, but that history doesn’t often treat philosophy as it relates to science, except perhaps so far as it explains issues in a manner that treats Epicurean materialism as true a priori. However, the sciences would produce valid and useful knowledge even if there were an immaterial aspect to reality. Christians don’t seek to dictate the answers science can provide. Rather, we seek to interpret the results in order to provide what science by its nature can’t provide: a true story of meaning and purpose.
If there is a conflict between Science and Religion, it’s because scientists and religious thinkers frequently make border incursions into each other’s territory (he said hypocritically). If Church leaders erred in forcing Galileo to keep quiet about the heliocentric solar system, it’s equally true that Galileo erred in obtruding theological speculations outside his competence. Perhaps we need a no-man’s-land between the two fields, patrolled by scientific specialists armed with second doctorates in philosophy. Maybe then scientists and theologians can get on with doing what each does best.
Update: February 13, 2010
The even shorter version of Hawking's fallacy is this:
"Nothing" means nothing ... not even laws of physics, which only express how something interacts with something else.
Delenda est Partu Meditato
 Ontology is the area of philosophy that concerns itself with the nature of being.
 Being isn’t limited to animals. Rather, it refers to something that exists, whether animate or not: a being is something that is.
 A being of reason is a being whose existence is postulated as an explanation or as part of an explanation.
 See “Infinite regress” (http://en.wikipedia.org/wiki/Infinite_regress).
 I characterize the uncreated indestructibility of matter an article of faith because, while it may be necessary for philosophical materialism, it isn’t necessary for astrophysics.
 The “god of the gaps” argument postulates that belief in gods arose solely from the need to explain natural phenomena. It’s a “straw man” fallacy because, while gods have been invoked to explain certain events, people have done so even when they could see a chain of natural causality; the gods, they have believed (and still believe), set the chain into motion.