David Berlinski - The Devil's Delusion

“It is superfluous to suppose,” Aquinas argues, “that what can be accounted for by a few principles has been produced by many.” This constant is now familiar as Occam’s Razor, even though William of Occam lived and wrote after Aquinas’s death.

“But it seems, ” Aquinas at once adds, “that everything we see in the world can be accounted for by other principles, supposing that God did not exist.”

Other principles?

Just so. “All natural things can be reduced to one principle, which is nature, and all voluntary things can be reduced to one principle, which is human reason, or will.”

It follows, Aquinas concludes provisionally, that “[t]here is no reason to suppose God’s existence.”

This is a conclusion that Aquinas is prepared to reject with all the force of his faith and genius. The existence of God may be demonstrated; it is subject to proof, and if not proof, then to argument. It follows that not everything in nature can be accounted for by “other principles.” The economies of thought offered by Occam’s Razor are an illusion.

We understand things in nature, Aquinas observes, by grasping as best we can causes and their effects: the match that lights the fire, the chill that sets one’s teeth to chattering, the water that slakes thirst. “In the world of sense,” as Aquinas says, “there is an order of efficient causes.” But just as no man can be his own father, no effect can be its own cause. A series of effects preceded by their causes forms a luminous metaphysical trail going backward into the past, because, as Aquinas argues, causes must precede their effects.

Can a series of this sort be infinitely continued, so that it simply disappears into the loom of time?

Aquinas argues that when it comes to causes, “it is not possible to go on to infinity, because in all…causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate cause.”

If a series of causes does not start, it cannot get going, and if it does not get going, then there will be no intermediate causes, and if there are no intermediate causes, then over here, where we have just noticed that a blow has caused a bruise, there is no explanation for what is before our eyes. Either there is a first cause or there is no cause at all, and since there are causes at work in nature, there must be a first. The first cause, Aquinas identified with God, because in at least one respect, a first cause shares an important property of the divine: It is uncaused.

This is a weak but not an absurd argument, and while Aquinas’s conclusion may not be true, objections to his argument are frequently inept. Thus Richard Dawkins writes that Aquinas “makes the entirely unwarranted assumption that God is immune to the regress.” It is a commonly made criticism. Lumbering dutifully in Dawkins’s turbulent wake, Victor Stenger makes it as well. But Aquinas makes no such assumption, and thus none that could be unwarranted. It is the conclusion of his argument that causes in nature cannot form an infinite series. If they are prepared to reject this conclusion, Dawkins and Stenger must show that the argument on which it depends is either invalid or unsound. This they have not done.

A far better objection has long been common in the philosophical literature: While an infinite series of causes has no first cause, it does not follow (does it?) that any specified effect is without a cause. Never mind the first cause. This blow has caused that bruise. The chain of causes starting with the blow may be chased into the past to any finite extent, but no matter how far back it is chased, effects will always have causes. Why, then, is that first cause so very important?

But this is a counterargument at which common sense is inclined to scruple. Seeing an endless row of dominoes toppling before our eyes, would we without pause say that no first domino set the other dominoes to toppling?

Really?

The give-and-take of these arguments is worthy of respect, but it no longer compels attention. In the eight hundred years following the publication of the Summa, the philosophers have had their say, but they have been overtaken by events. The argument that Aquinas wished to make on metaphysical grounds has been made in other terms and in other ways, and in particular a form of the cosmological argument has appeared in the very place one might least expect it to appear: contemporary physical cosmology.

The universe, orthodox cosmologists believe, came into existence as the expression of an explosion—what is now called the Big Bang. The word explosion is a sign that words have failed us, as they so often do, for it suggests a humanly comprehensible event—a gigantic explosion or a stupendous eruption. This is absurd. The Big Bang was not an event taking place at a time or in a place. Space and time were themselves created by the Big Bang, the measure along with the measured. If the image of an ordinary explosion is inadequate to the Big Bang, the words themselves— the Big Bang —have by themselves a disturbing power. They suggest the most ancient of human intuitions, and that is the connection between sexual and cosmic energies. The words may have been chosen whimsically; they were not chosen accidentally.

Whatever its name, as far as most physicists are concerned, the Big Bang is now a part of the established structure of modern physics. From time to time, it is true, the astrophysical journals report the failure of observation to confirm the grand design. It hardly matters. The physicists have not only persuaded themselves of the merits of Big Bang cosmology, they have persuaded everyone else as well. The Big Bang has come to signify virtually a universal creed, men and women who know nothing of cosmology convinced that the rumble of creation lies within reach of their collective memory.

If the Big Bang expresses a new idea in physics, it suggests an old idea in thought: In the beginning God created the heaven and the earth. This unwelcome juxtaposition of physical and biblical ideas persuaded the astrophysicist Fred Hoyle, an ardent atheist, to dismiss the Big Bang after he had named it. In this he was not alone. Many physicists have found the idea that the universe had a beginning alarming. “So long as the universe had a beginning,” Stephen Hawking has written, “we could suppose it had a creator.” God forbid! Nonetheless, there is a very natural connection between the fact that the universe had a beginning and the hypothesis that it had a creator. It is a connection so plain that, glowing with its own energy, it may be seen in the dark. Although questions may be raised about what it means, the connection itself cannot be ignored. “The best data we have concerning the big bang,” the Nobel laureate Arno Penzias remarked, “are exactly what I would have predicted, had I nothing to go on but the five books of Moses, the Psalms, the Bible as a whole.”

Remarks such as this traveled far afield. They were repeated gratefully by men and women persuaded that at last cosmology had made some sort of sense. They appeared in the New York Times. Physicists quickly came to their senses. They discovered elaborate reasons to avoid the obvious, not least of which, the fact that the obvious was obvious. For more than a century, physicists had taken a manful pride in the fact that theirs was a discipline that celebrated the weird, the bizarre, the unexpected, the mind-bending, and the recondite. Here was a connection that any intellectual primitive could at once grasp: The universe had a beginning, thus something must have caused it to begin. Where would physics be, physicists asked themselves, if we had paid the slightest attention to the obvious?