Jerry Coyne can always be counted on for a cartoonish view on modern monotheist religions — and so too on ancient polytheist ones. Writing at Why Evolution Is True, the University of Chicago biologist chides British Chief Rabbi Jonathan Sacks, an incomparably more subtle and serious thinker than Dr. Coyne, for observing that giving up religion had a deleterious effect on Greek morals. But of course it’s Sacks who is correct here. Coyne goggles:

[Sacks] also claimed, bizarrely, that the decline of ancient Greece can be attributed to its reliance on pre-Enlightenment values and the absence of religion, claiming that it might not have fallen had the people believed in the supernatural. (I wonder, then, what Apollo, Zeus, and Athena were.)

But minus the reference to the Enlightenment, that is exactly what the 2nd-century BC Greek historian Polybius observed in his Histories. Comparing Roman success with Greek decline, he attributed the latter to his countrymen’s having jettisoned religious piety in a way the people of Rome, to that point, had not done. Here is Polybius in Chapter 6 of the Histories:

The most important difference for the better which the Roman commonwealth appears to me to display is in their religious beliefs.
For I conceive that what in other nations is looked upon as a reproach, I mean a scrupulous fear of the gods, is the very thing which keeps the Roman commonwealth together. To such an extraordinary height is this carried among them, both in private and public business, that nothing could exceed it. Many people might think this unaccountable; but in my opinion their object is to use it as a check upon the common people. If it were possible to form a state wholly of philosophers, such a custom would perhaps be unnecessary. But seeing that every multitude is fickle, and full of lawless desires, unreasoning anger, and violent passion, the only resource is to keep them in check by mysterious terrors and scenic effects of this sort. Wherefore, to my mind, the ancients were not acting without purpose or at random, when they brought in among the vulgar those opinions about the gods, and the belief in the punishments in Hades: much rather do I think that men nowadays are acting rashly and foolishly in rejecting them. This is the reason why, apart from anything else, Greek statesmen, if entrusted with a single talent, though protected by ten checking-clerks, as many seals, and twice as many witnesses, yet cannot be induced to keep faith: whereas among the Romans, in their magistracies and embassies, men have the handling of a great amount of money, and yet from pure respect to their oath keep their faith intact. And, again, in other nations it is a rare thing to find a man who keeps his hands out of the public purse, and is entirely pure in such matters: but among the Romans it is a rare thing to detect a man in the act of committing such a crime.

Though Polybius sounds like a pragmatist, even a cynic, on religion, the basic point stands and directly refutes Jerry Coyne.