“The math to prove all the foregoing is admittedly abstruse, although, ironically, the Wreeds intuitively came to an identical model. But the theory of everything made numerous predictions that have subsequently been confirmed experimentally; it has withstood every test it has been put to. And when we found that we could not retreat into the notion that this universe is one of vast number, the argument for intelligent design became central to Forhilnor thought. Since this is one of a maximum of just nine universes that have ever existed, for it to have these highly improbable design parameters implies they were indeed chosen by an intelligence.”

“Even if maybe, perhaps, the four — excuse me, the five — fundamental forces have seemingly wildly improbable values,” I said, “that still is only five separate coincidences, and, although granted it is hugely unlikely, five coincidences could indeed occur by random chance in just nine iterations.”

Hollus bobbed. “You have intriguing tenacity,” he said. “But it is not just the five forces that have seemingly designed values; many other aspects of the way the universe works appear likewise to have been minutely adjusted.”

“For instance?”

“You and I are made up of heavy elements: carbon, oxygen, nitrogen, potassium, iron, and so on. Practically the only elements that existed when the universe was born were hydrogen and helium, in a roughly three-to-one ratio. But in the nuclear furnaces of stars, hydrogen is fused into heavier elements, producing carbon, oxygen, and so on up the periodic table. All of the heavy elements that make up our bodies were forged in the cores of long-dead stars.”

“I know. ‘We are all star-stuff,’ as Carl Sagan used to say.”

“Precisely. Indeed, scientists from your world and mine refer to us as carbon-based lifeforms. But the fact that carbon is produced by stars depends critically on the resonance states of the carbon nucleus. To produce carbon, two helium nucleuses must stick together until they are struck by a third such nucleus — three helium nucleuses provide six neutrons and six protons, the recipe for carbon. But if the resonance level of carbon were only four percent lower, such intermediate pair-bonding could not occur, and no carbon would be produced, making organic chemistry impossible.” He paused. “But just producing carbon, and other heavy elements, is not enough, of course. Those heavy elements are here on Earth because some fraction of stars — what is the word? When a large star explodes?”

“Supernova,” I said.

“Yes. Those heavy elements are here because some fraction of stars become supernovas, spewing their fusion products into interstellar space.”

“And you’re saying that the fact that stars do go supernova is something that also must have been designed by a god?”

“It is not as simplistic as that.” A pause. “Do you know what would happen to Earth if a nearby star became a supernova?”

“If it were close enough, I suppose we’d be fried.” In the 1970s, Dale Russell had favored a nearby supernova explosion as the cause of the extinctions at the end of the Cretaceous.

“Exactly. If there had been a local supernova anytime in the last few billion years, you would not be here. Indeed, neither of us would be, since our worlds are quite close together.”

“So supernovas can’t be too common, and—”

“Correct. But neither can they be too rare. It is shockwaves made by supernova explosions that cause planetary systems to start to coalesce from the dust clouds surrounding other stars. In other words, if there had been no supernovas ever anywhere near your sun, the ten planets that orbit it would never have formed.”

“Nine,” I said.

“Ten,” repeated Hollus firmly. “Keep looking.” His eyestalks waved. “Do you see the quandry? Some stars must become supernovas in order to make heavy elements available for the formation of life, but if too many do, they would wipe out any life that got started. Yet if not enough do, there would be precious few planetary systems. Just as with the fundamental physical constants and the resonance levels of carbon, the rate of supernova formation again seems precisely chosen, within a very narrow range of possibly acceptable values; any substantial deviation would mean a universe without life or even planets.”

I was struggling for footing, for stability. My head ached. “That could just be a coincidence, too,” I said.

“It is either coincidence piled on top of coincidence,” said Hollus, “or it is deliberate design. And there is more. Take water, for instance. Every lifeform we know of evolved in water, and all of them require it for their biological processes. And although water seems chemically simple — just two hydrogen atoms bound to an oxygen — it is, in fact, an enormously unusual substance. As you know, most compounds contract as they cool and expand as they heat. Water does this, too, until just before it starts to freeze. It then does something remarkable: it begins to expand, even as it grows colder, so that by the time it does freeze, it is actually less dense than it was as a liquid. That is why ice floats instead of sinking, of course. We are so used to seeing that, whether it is ice balls in a beverage or a skin of ice on a pond, that we usually give it no thought. But other substances do not do that: frozen carbon dioxide — what you call dry ice — sinks in liquid carbon dioxide; a lead ingot will sink in a vat of molten lead.

“But water ice floats — and if it did not, life would be impossible. If lakes and oceans froze from the bottom up, instead of the top down, no sea-floor or lake-bottom ecologies would exist outside equatorial zones. Indeed, once they had started freezing, bodies of water would freeze solid and remain solid forever; it is currents moving unfettered beneath surface ice that promotes melting in the spring — that is why glaciers, which have no such currents beneath them, exist for millennia on dry land adjacent to liquid lakes.”

I returned the eurypterid fossil to its drawer. “I grant that water is an unusual substance, but—”

Hollus touched his eyes together. “But this strange expanding-before-freezing is hardly the only remarkable thermal property water has. In fact, it has seven different thermal parameters, all of which are unique or nearly so in the chemical world, and all of which independently are necessary for the existence of life. The chances of any of them having the aberrant value it does must be multiplied by the chances of the other six likewise being aberrant. The likelihood of water having these unique thermal properties by chance is almost nil.”

“Almost,”I said, but my voice was starting to sound hollow, even to me.

Hollus ignored me. “Nor does water’s unique nature end with its thermal properties. Of all substances, only liquid selenium has a higher surface tension than does water. And it is water’s high surface tension that draws it deeply into cracks in rocks, and, of course, as we have noted, water does the incredible and actually expands as it freezes, breaking those rocks apart. If water had lower surface tension, the process by which soil is formed would not occur. More: if water had higher viscosity, circulatory systems could not evolve — your blood plasma and mine are essentially sea water, but there are no biochemical processes that could fuel a heart that had to pump something substantially more viscous for any appreciable time.”

The alien paused. “I could go on,” he said, “talking about the remarkable, carefully adjusted parameters that make life possible, but the reality is simply this: if any of them — any in this long chain — were different, there would be no life in this universe. We are either the most incredible fluke imaginable — something far, far more unlikely than you winning your provincial lottery every single week for a century — or the universe and its components were designed, purposefully and with great care, to give rise to life.”