It could have been one of those grim science-vs.-religion debates, filled with blunt diatribes against superstition and scientific idolatry. Instead, physicist-author Steven Weinberg and physicist-priest John Polkinghorne traded sharp observations over the topic of the day: Is the universe designed?
Thursday's debate was part of this week’s “Cosmic Questions” symposium, conducted at the National Museum of Natural History in Washington. Moderator Owen Gingerich, an astronomer at the Smithsonian Astrophysical Observatory and a Harvard professor, noted that it was in the same auditorium that the famous 1920 Shapley-Curtis debate on the scale of the universe was held.
The most recent debate wasn’t likely to spur any conversions or apostasies, but it did serve as an thoughtful exposition on why the cosmos’ physical and chemical processes seem so finely tuned to allow for life, the universe and everything.
In fact, Weinberg joked that he and Polkinghorne, a particle physicist who became an Anglican priest and is a former president of Queens’ College at Cambridge, were so attuned to the subject of God in the universe that they were not representative of their fields.
“Many people claim to be religious, and when you ask them what they believe in, you find that they have no beliefs to speak of,” said Weinberg, a physics professor at the University of Texas at Austin. On the other side, he observed that “most scientists are not atheists, because they don’t think about it enough to be atheist.”
Hand of the creator?
Some observers have pointed to the “fine-tuning” of the constants found in nature as proof that a divine hand is at work. For example, if the total energy level of carbon-12 were 1 percent higher, then the production of carbon in chemical reactions would be greatly diminished — and as a result, life would not have developed in the universe.
But Weinberg said the margin of error is actually 25 percent when other chemical factors were taken into account, “It’s not very impressive fine-tuning at all,” he said.
Is it mere chance, then, that the universe permitted the development of beings who can agonize over the meaning of the universe? Polkinghorne preferred to think this demonstrated that a metaphysical, moral order existed alongside the physical order. But Weinberg instead turned to a concept known as the anthropic principle. According to this principle, we observe conditions that permit our existence precisely because if the conditions were any different, we wouldn’t be around to observe them.
“It may be that in the great majority of planets where life arises and evolves, only that measure of intelligence evolves which is strictly necessary for breeding and eating,” he said. “However, those animals are not discussing the issue, and the fact that we are discussing the issue creates a bias.”
Any moral order is mere convention, he said.
“There is a moral order,” he said. “It is wrong to torture children, and the reason it’s wrong to torture children is because I say so. And I don’t mean much more than that. Not only I say so, but John says so, probably most of us say so. But it is not a moral order out there, it is something we impose — and bully for us.”
The problem of evil
The Creator took some hard knocks from Weinberg for permitting the existence of evil and suffering, and indeed Polkinghorne acknowledged that the issue posed the “greatest difficulty of theism,” with no simple explanation available. But the alternative — a micromanaged universe — was even more abhorrent to him.
“The evolutionary exploration … is understood theologically as a creation which is not the puppet theater of the cosmic tyrant, but is a creation allowed to be and to make itself,” he said. “If there is a God who is the God of love, then creation could not be just a divine puppet theater, for the gift of love is always the gift of a due independence, as wise parents know in relation to their children.”
Both debaters acknowledged that there are plenty of unknowns yet to be resolved — in science as well as in religion. Weinberg even allowed as how God could strike him down with a flaming sword as he sat on the stage.
“Could I just say that if, God forbid, a flaming sword were to come and decapitate Steve before our very eyes, that would pose a very big theological problem,” Polkinghorne deadpanned, “because that would be the capricious act of a magical vengeful God, and that’s not the god of my belief. …”
“Well, it would pose not only a theological problem, but a janitorial problem,” Weinberg joked.