Robert Sawyer - Calculating God

“My friend identified hundreds of genes that seem to be the same as those in life from this planet. The gene that creates hemoglobin, for instance.”

“There are only a limited number of possible chemicals that can be used to carry oxygen in the bloodstream.”

“I guess she was expecting something more — well, alien.”

“I am as alien a being as you are every likely to encounter,” said Hollus. “That is, the difference between your body plan and mine is as great as we have ever seen. There are practical engineering constraints on how weird life can get, after all, even” — and here he raised one of his six-fingered hands and did a Vulcan salute — “if your filmmakers seem incapable of coming close to the variety possible.”

“I suppose,” I said.

Hollus bobbed. “The minimum number of genes required for life is about 300,” he said. “But that quantity is sufficient only for truly primitive creatures; most eukaryotic cells share a core group of about three thousand genes — you find them in everything from single-celled lifeforms to elaborate animals like ourselves, and they are the same, or almost the same, on every world we have looked at. On top of that, there are 4,000 additional genes that are shared by all multicellular lifeforms, which encode proteins for cell-to-cell adhesion, signaling between cells, and so on. There are thousands more shared by all animals with internal skeletons. And thousands more beyond that are shared by all warm-blooded animals. Of course, if your friend keeps searching, she will find tens of thousands of genes in Forhilnor DNA that have no counterparts in Earthly lifeforms, although, naturally, it is easier to match genes than to find unfamiliar ones. But there really are only a few possible solutions to the problems posed by life, and they recur on world after world.”

I shook my head. “I wouldn’t have expected life from Beta Hydri to use the same genetic code as life on Earth does, let alone any of the same genes. I mean, there are even some variations in the code here: out of the sixty-four codons, four have different meanings in mitochondrial DNA than they do in nuclear DNA.”

“All lifeforms we have examined share essentially the same genetic code. It surprised us at first, as well.”

“But it just doesn’t make sense,” I said. “Amino acids come in two isomers, left– and right-handed, but all life on Earth uses only the left-handed versions. For starters, it should be a fifty-fifty shot for any two ecosystems to both use the same orientation. And there should be only a one-in-four chance that three ecosystems — yours, mine, and the Wreeds’ — would use the same one.

“Indeed,” said Hollus.

“And even just taking the left-handed kind, there are still over a hundred different amino acids — but life on Earth only uses twenty of them. What are the chances that life on other worlds would use those exact same twenty?”

“Pretty darn remote.”

I smiled at Hollus; I’d expected him to give me a precise statistical answer. “Pretty darn remote indeed,” I said.

“But the choice is not random; God designed it that way.”

I let out a long sigh. “I just can’t buy that,” I said.

“I know,” said Hollus, sounding as though he despaired for my ignorance. “Look,” he said after a time, “I am not a mystic. I believe in God because it makes scientific sense for me to do so; indeed, I suspect God exists in this universe because of science.”

My head was starting to hurt. “How’s that?”

“As I said earlier, our universe is closed — it will eventually collapse back down in a big crunch. A similar event happened after billions of years in the universe that preceded this one — and with billions of years, who knows what phenomenal things science might make possible? Why, it might even make it possible for an intelligence, or data patterns representing it, to survive a big crunch and exist again in the next cycle of creation. Such an entity might even have science sufficient to allow it to influence the parameters for the next cycle, creating a designer universe into which that entity itself will be reborn already armed with billions of years worth of knowledge and wisdom.”

I shook my head; I’d expected something better than a riff on “it’s turtles all the way down.” “Even if that’s so,” I said, “that hardly solves the problem of whether or not God exists. You’re just pushing the creation of life back one step farther. How did life start in the universe before this one?” I frowned. “If you can’t explain that, you haven’t explained anything.”

“I do not believe that the being who is our God was ever alive,” said Hollus, “in the sense of being a biological entity. I suspect this is the first universe in which biology and evolution have ever taken place.”

“Then what is it, this God-being?”

“I see no evidence here on Earth that you have yet achieved artificial intelligence.”

That seemed a non sequitur to me, but I nodded. “That’s right, although a lot of people are working on it.”

“We do have self-aware machines. My starship, the Merelcas, is one such. And what we have discovered is this: intelligence is an emergent property — it appears spontaneously in systems of sufficient order and complexity. I suspect that the being which is now the God of this universe was a noncorporeal intelligence that arose through chance fluctuations in a previous universe devoid of biology. I believe this being, existing in isolation, sought to make sure that the next universe would teem with independent, self-reproducing life. It seems unlikely that biology could have started in any randomly generated universe on its own, but a localized space-time matrix of sufficient complexity to develop sentience could reasonably be expected to arise by chance after only a few billion years of quantum fluctuations, especially in universes unlike this one in which the five fundamental forces have less divergent relative strengths.” He paused. “The suggestion that essentially a scientist created our current universe would explain the long-standing philosophical conundrum of why this universe is indeed comprehensible to the scientific mind; why Forhilnor and human abstractions, such as mathematics and induction and aesthetics, are applicable to the nature of the reality. Our universe is scientifically understandable because it was created by a vastly advanced intelligence who used the tools of science.”

It was staggering to think that intelligence could arise more easily than life itself could — and yet we really didn’t have a good definition of intelligence; every time a computer seemed to succeed at duplicating it, we simply said that that’s not what we meant by the term. “God as a scientist,” I said, tasting the thought. “Well, I guess any sufficiently advanced technology is indistinguishable from magic.”

“Pithy,” said Hollus. “You should write that down.”

“I don’t think it’s original to me. But what you’re proposing is just that — a proposal. It doesn’t prove the existence of your God.”

Hollus bobbed his torso. “And just what sort of evidence would convince you?”

I thought about that for a while, then shrugged. “A smoking gun,” I said.

Hollus’s eyes moved to their maximum separation. “A what?”

“My favorite genre of fiction is murder mysteries, and—”

“I am astounded that humans take pleasure in reading about killing,” said Hollus.

“No, no,” I said. “You’ve got it wrong. We don’t enjoy reading about killing; we enjoy reading about justice — about a criminal, no matter how clever, being proved guilty of the crime. And the best proof in a real murder case is to find the suspect holding the smoking gun — actually holding the weapon used to commit the crime.”