When the French scientist Pierre Laplace first explained his nebular theories to Napoleon, the emperor posed to him a single question. “Where is there room in all this for God?” To which Laplace famously replied, “I have no need for that hypothesis.”

Christopher Hitchens invokes Laplace’s reply in his new book God Is Not Great. In a sense, Laplace supplies the central argument for the kind of naturalism that Hitchens espouses. The world can be entirely understood on the basis of natural laws and events. Why call upon God when he is entirely superfluous in order to make sense of the world?

As Hitchens’ title suggests, his argument goes further than this. God is not merely unnecessary, he is “not great.” The subtitle is even harsher, “How Religion Poisons Everything.” Everything? Yes, Hitchens would have us believe that whatever religion touches it corrupts and inflames.

Hitchens is an iconoclast, as is indicated by one of his earlier books, a harshly critical biography of Mother Teresa called The Missionary Position. While I found that book quite foolish and distasteful, I found myself applauding some of Hitchens’ pungent rhetoric in this one. There is plenty of room for even Christians to be outraged by some of the things going on in the churches—the blatant money-grubbing, the jaw-dropping hypocrisy, the sex scandals that would make even Hugh Hefner blush—and Hitchens is unsparing in his expose of these offenses.

When Hitchens turns to larger political conflicts, however, his arguments droop. He strains to show that the clash between the Catholics and the Protestants in Northern Ireland is motivated by religion, without answering the objection that the two groups seem to be fighting not about doctrine but about land and political autonomy. He baptizes the warfare in the Balkans as “religious” rather than “ethnic” cleansing, even though these feuds are rooted in tribe and blood. Religious differences are only incidental.

Hitchens implausibly suggests that if messianic rabbis and mullahs could be kept out of the Palestinian conflict, the issue would have been settled “decades ago.” As a mater of fact, both Zionism and Palestinian nationalism are largely secular movements and the conflict has always been based on a simple, non-religious question: who owns this land? Hitchens even seeks to portray the Shia-Sunni conflict in Iraq as a clear strike against religion. In reality the theological differences between Shia and Sunni are non-existent and the real basis of the sectarian warfare is entirely political and power-driven.

The title of Hitchens’ book is derived from the Muslims. It is a negation of the Arabic slogan “Allahu Akbar” which means “God is great.” Hitchens is, of course, right about the pernicious way in which the radical Muslims use religion to justify their murderous acts of terrorism. But Hitchens never shows that Islam itself is the problem. Most of his anti-religious polemic is in any case directed at Christianity, and here Hitchens is equally ineffective. He doesn’t even ponder the central question raised by his title. If he’s right that all religions are false and God is a figment of the human imagination, why should imaginary things cause so many problems? Dreams and unicorns don’t “poison everything” so why should deities?

Hitchens seeks to place himself squarely in the scientific tradition, arguing that the operations of the universe can be worked out using the theories of Darwin and Einstein and “no divine plan, let alone angelic intervention, is required. Everything works without that assumption.” This is a serious point, which gave Napoleon pause and it should us as well. But here too Hitchens does not even begin to sustain Laplace’s proposition.

Modern science has discovered that the universe, far from existing eternally, had a beginning. Not only matter but space and time itself came into existence around 15 billion years ago in the fiery burst that scientists term the Big Bang. The laws of physics themselves originated at that point, and those laws were inoperative “before” the founding moment. So what is the secular explanation for how the universe and its laws came into existence? Is there a natural explanation for nature’s own origin? If so, what is the evidence for it? Hitchens supplies no such theory and no supporting evidence. His rejection of the God hypothesis seems nothing more than an assertion of atheist dogma.

In recent decades, scientists have found innumerable ways in which our universe—not just our planet but the entire universe—is narrowly tailored to permit life. Change the variables of nature by an infinitesimal amount and this would be a very different universe without observers to perceive and study it. As physicist Freeman Dyson puts it, with an intended mystical touch, the universe behaves as though it knew we were coming! So why are the laws constructed in such a way that we are here to discover them? It’s possible that there is a convincing natural explanation, but Hitchens certainly does not produce one. Once again the God hypothesis seems unavoidable.

Now consider man, undoubtedly a product of natural selection, but also possessing qualities such as the ability to tell right from wrong that are unexplained by Darwin and his followers. Neo-Darwinists have labored hard to offer an evolutionary basis for altruism, explaining parental love and loyalty to one’s own tribe in terms of Richard Dawkins’ “selfish gene.” It’s an ingenious attempt, but it doesn’t account for purely unselfish acts, as when a fellow gives up his seat in the bus to a perfect stranger, or when Mother Teresa devotes herself to improving the lives of the destitute in India. In what way do those actions benefit the selfish genes?

Further, altruism is only one aspect of morality. There is within us all a moral law that speaks to us gently but firmly, urging though not compelling us to do what is right, even when such a course conflicts with our self-interest. If natural selection cannot account for this moral law, where does it come from? I am not saying that science will never explain this, I am saying that science cannot explain it now. It seems much more reasonable, based on existing evidence, to believe that moral laws derive from a divine legislator than to embrace Hitchens’ promissory atheism: one day we’ll figure out a natural way to account for all this.

Thanks to the astounding discoveries of modern science, I think the God hypothesis has a lot more going for it today than it did in the eighteenth century, when Laplace presented his theories to Napoleon. The appeal of Hitchens is not his scientific rationalism (he is utterly out of his element here) but rather his witty truculence. Hitchens, like Mencken, seems to despise religion, although Mencken was at least candid enough to title one of his books “Prejudices.” I like Hitchens, whom I’ve known for more than two decades, and I wish we had him in the camp of the believers. His latest tract is, well, let’s just say it’s “not great.”