The summit of Mount Stephenson

How do men of science explain God? Or, conversely, how do men of faith come to terms with science? Is the miraculous complexity unveiled by modern biology and chemistry and physics proof of an awesome creator, or the opposite?

"The Baroque Cycle" contains many things, some of which, like the extended analysis of the blueprint of the Tower of London that drags on forever in "The System of the World," are less interesting than others. But like a compass whose needle continually swings back to point to north, no matter how many times it is jostled, Stephenson's trilogy keeps returning to an awesome preoccupation: the truth about God and the universe.

Smart people often disagree on this topic; really smart people are often obsessed with it. If we are to trust Stephenson, and I see no reason not to, Gottfried Leibniz and Isaac Newton were two of the smartest people ever. Both were men of profound faith, and yet they were responsible for scientific and philosophical discoveries that, in the centuries after them, fundamentally shook Western civilization's faith in that omnipotent deity on high.

Newton and Leibniz have issues. There is, for one thing, the question of who invented "the calculus" first. The evidence leans Leibniz's way, but Newton will kowtow to no man. Oh, and then there's that trifling dispute as to how the universe works.

The quest for understanding the underlying principles of everything runs through each volume of "The Baroque Cycle," a kind of meta-umbrella encompassing all the other sub-themes (to recap: birth of modern finance, biology and chemistry; transition from monarchy to representative government; alchemical search for eternal life, et cetera). But in "The System of the World" this search becomes most explicit.

In Volume 3, the philosophical becomes personal when Waterhouse arranges a debate between Leibniz and Newton in the presence of the perspicacious Princess Caroline of Hanover (wife of George I, the first Hanoverian king of England).

The chapter, titled "Philosophick Showdown at Leicester House," delivers a scene that action fans might find paralyzing, literary critics might sneer at, and only a very small subset of geekily arrogant writers would even attempt (Thomas Pynchon and Richard Powers come to mind). Two of history's greatest geniuses put their unified-theories-of-existence cards on the table. The sniping is fast and furious. At stake is not just truth itself, but as Leibniz accuses Newton, the potential crime of "spreading doctrines that incline others toward Atheistical views." (The slur, Newton says, more properly should be aimed at Leibniz.)

A typical exchange goes something like this:

"By no means," said Leibniz. "I say only that, though the machine of the body obeys deterministic laws, it does so in accordance with the desires and dictates of the soul, because of the pre-established harmony."

"Of that, we must needs hear more, for it is very difficult to understand," said the Princess.

"Chiefly because it is wrong!" said Sir Isaac.

Caroline now had to literally step between the two philosophers.

Much as the image of Leibniz and Newton as WWF wrestlers body-slamming each other amuses, the terms of this debate are challenging to comprehend. Does the soul have a mechanical, deterministic basis, or doesn't it? What does this have to do with Leibniz's theory of monads and Newton's theory of gravitation? It hardly seems worth mentioning that the two philosophers do not come to agreement.

And what of that cutting accusation, that one or the other philosopher's discoveries are turning people away from God? If the Enlightenment, which these two men are partial architects of, is a process that unlocked humanity from a state of blind faith into knowing doubt, then aren't both men guilty?

My own feeble grounding in natural philosophy, not to mention advanced mathematics and physics, does not equip me to evaluate the debate between Leibniz and Newton from a position of authority. The only thing I can discern for sure is that two very smart men utterly disagree with each other.

Could that be the point -- that there is no consensus? This is not to say that Stephenson is some kind of postmodern relativist who believes everything is a social construct. Far from it. In the past, Stephenson has saved some of his most cutting scorn for such types -- like all good engineers, Stephenson has always conveyed the sense that you can figure out how things work, and indeed, the whole point of "The Baroque Cycle" is to wallow as thoroughly as possible in the sights, smells and sounds of a period in history where people were figuring out how things really worked.

But that doesn't mean that they got the final answer, or even that any such answer is possible, or that any new system is perfect.

At the very end of his epic, Waterhouse reflects that even a "flawed and doomed" system is better than no system at all. Here, and elsewhere in this final volume, there is some ominous foreshadowing of just where men of reason may end up leading the world: the horrors of 20th century fascism and totalitarianism, the manifest failures of democracy and capitalism, the heightening tension between science and faith that plagues us to this day.

Surely, if the natural philosophers of the Enlightenment were so smart, they could have done better? Or could have declined to chomp at the forbidden apple?

But that's not how science works. It's not how engineers or programmers work, either. There is no perfect system -- you just keep tinkering until you get something that works well enough, and when that breaks down you come up with a new improved model. The effort of improvement is its own reward. In "Cryptonomicon," Avi Halaby, Randy Waterhouse's partner, is trying to come up with a scheme using computers, networks and cryptography that will prevent future Holocausts. It's not clear that it will have any real chance of success, but still, one must try.

That effort at understanding, at tinkering with the system, of looking through the microscope, of striving for first principles even though full knowledge may never be attained, is the preoccupation of Stephenson's characters in "The Baroque Cycle." One senses his admiration on every page, and his challenge: to follow their example, to tinker some more, to reform the coinage, figure out a unified theory, end slavery, build cool computers and, above all, go for the gold.

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