RELIGION WITHOUT GOD. By Ronald Dworkin. Harvard University Press. 180 pages. $17.95.

To be religious is to believe in God, pray, go to church, that sort of thing. At least, that's the popular conception of religion, which holds that humankind is part of a grand, miraculous and eternal creation, that the divine is discernible and, under the right circumstances, achievable.

Against this notion the secular humanists fight. They argue that there's no physical or scientific evidence for God, Heaven or Hell, that belief in the supernatural is superstition (or worse) and that religion obviates human agency, leaving an unjustifiable moral loophole permitting the faithful to forego their earthly responsibilities.

Most religious people don't want to give up their faith, so the arguments of the secularists aren't likely to make much of a dent. Similarly, most atheists won't suddenly subscribe to a religious tradition, so attempts at proselytizing tend to be futile. The two sides, separated by a chasm of misunderstanding, talk right past one another.

Ronald Dworkin, the much-respected legal philosopher who died earlier this year, transformed a lecture into a short book recently published by Harvard University Press called "Religion Without God," which essentially sidesteps the regular theist vs. atheist debate to argue something altogether original and refreshing: that the religious impulse is (a) widely shared and (b) much bigger than a belief in God.

"Religion is a deep, distinct, and comprehensive worldview: it holds that inherent, objective value permeates everything, that the universe and its creatures are awe-inspiring, that human life has purpose and the universe order," Dworkin writes in the introduction. "A belief in a god is only one possible manifestation or consequence of that deeper worldview."

Since that value is independent - religion only serves to reinforce it - a commitment to this underlying objective reality is available to both believers and nonbelievers, Dworkin argues. "So theists share a commitment with some atheists that is more fundamental than what divides them, and that shared faith might therefore furnish a basis for improved communication between them."

Religious people surely experience drudgery, just as atheists are capable of appreciating profound mystery. What they have in common - or should have in common - is a devotion to moral truth.

Convictions of value are the common glue of humanity, Dworkin writes, and this idea is so appealing and so thoughtfully rendered in "Religion Without God," that it is hard to find any fault with his logic, unless you happen to be a die-hard naturalist who believes that there is nothing, not even moral truth, beyond what nature provides, that all else is illusion.

Dworkin does not dismiss religion; he acknowledges that some people will gaze upon the Grand Canyon and attribute its beauty to God. Others will stand at its edge and marvel at the geology. Beauty is not necessarily evidence of the divine, Dworkin writes. Take the Taj Mahal, with its stunning symmetry: its beauty (who would deny it?) is a result of mathematics.

A believer will retort that math itself is a product of God's divine creation. Fine, says Dworkin. But it is fair to propose that math is self-sufficient, or part of the universal order that transcends religion, needing no deity to legitimize it or deign it with what we might call the sublime.

But is beauty real? Is it our response to what we perceive as divinely inspired or is it a consequence of a different kind of inevitability, perhaps natural or human-caused? It is hard to imagine that Raphael's "Madonna of the Meadow," with its triangular composition and luminous coloring, should have been made differently, or that a Bach fugue is the product of chance.

Dworkin thinks that art is great when it conveys this sense of ineluctable destiny, and the idea can be expanded to include all we know. As the atheist Einstein said (using a religious metaphor), "God doesn't play dice with the universe."

This inevitability is evidence of something vaster than any particular religion, according to Dworkin, and proof that all people, regardless of affiliation or cultural inheritance, can find common ground. So when he uses the term "religious atheism," it is no contradiction. For Dworkin, one can be religious - susceptible to the awe-inspiring mysteries of the universe and the beauty that nature and human creativity provide - without believing in what he calls the Sistine God, the bearded figure painted by Michelangelo who, with the touch of his fingertip, made mankind.

"Religion Without God" is a tiny book, only 159 pages of text, that inexorably lays out in lucid terms Dworkin's moral philosophy. The logical argument he makes is itself an example of the sort of inevitable beauty he describes in chapter two, "The Universe."

The final short chapter is about death and immortality. It was written by a man who knew his time was up. And here, in these few last pages, Dworkin reveals the profound humanism that has informed his life's work. He believes, tenaciously, that there is objective ethical and moral truth, "a right way to live" that is independent of theistic assumptions, and therefore available to religious atheists.

"What matters most fundamentally to the drive to live well is the conviction that there is, independently and objectively, a right way to live," he writes. "In this most fundamental respect religious theists and religious atheists are at one. The existence or nonexistence of a god does not figure in the instinct of value that unites them. What divides them is science: they disagree about the best explanation of the truths of matter and mind, but it by no means follows that they disagree about the further truths of value."

And living well leads to its own kind of immortality. When one makes a perfect painting that speaks across the generations, or leaves a lasting mark on philosophical discourse, he is doing so in answer to human existence. These are achievements within life, but sometimes one's life itself, with its gestures large and small, its expressions of love, its useful consequences, is a noble achievement.

"If we do crave that kind of achievement, as I believe we should, then we could treat it as a kind of immortality," Dworkin concludes.

Reviewer Adam Parker is arts writer and book page editor for The Post and Courier.