Pity the poor agnostic these days, caught in the middle of an ever-widening gap between an increasingly assertive religious fundamentalism on one side, and on the other a new brand of atheism whose dogmatic certitude and zealous proselytizing make it appear more fundamentalist by the day. Where in the conflict between these two competing claims of absolute certainty—religious and scientific—is there room for the person willing to throw his hands in the air and say simply, “I don’t know?”

Enter into this chasm the journalist and host of KQED public radio’s nationally syndicated talk show Forum, Michael Krasny. Krasny’s new book, Spiritual Envy, is essentially an agnostic manifesto: an eloquent and deeply personal journey to find some kind of spiritual center in what has become an increasingly polarized debate about the role and function of religion in America.

Krasny has long considered himself to be an agnostic, and while that term has taken on multiple shades of meaning since it was coined by Thomas Huxley in 1876—there are theist agnostics and atheistic agnostics and a whole lot in between, Krasny writes—at the core of agnosticism is the notion of being “without knowledge.” Yet, as Krasny notes, Huxley used the term himself not to indicate merely lack of knowledge, but rather to imply that, when it comes to matters of the divine, knowledge (at the least the scientific kind) is simply unattainable.

“What, really, does it mean to call oneself agnostic,” Krasny asks, “other than to be unwilling or unable to yield to belief and allow it into one’s bloodstream?”

The fundamental problem with agnostics, as Krasny sees it, is that they “cannot help knowing [that] they do not know.”

It is a good question, and one that is rarely asked. Is agnosticism merely about uncertainty? Is it a matter of indecisiveness? Or, perhaps, it is simply spiritual laziness. After all, in our modern world of moralizing politicians, religious hypocrites, and holy warriors, the term “agnostic” has come to signify not so much “I don’t know,” as “I don’t care.”

The problem with Krasny is that he does, in fact, care. He not only wants to recover the scientific agnosticism of T.H. Huxley, Robert G. Ingersoll, and Bertrand Russell—what Krasny calls the “holy trinity of agnostics”—he seeks an ethical dimension to agnosticism that relies neither on the divine absolutism of religion nor on the biological determinism of science. In other words, he wants to provide a kind of “agnostic moral code” that people in the middle—those who do not know but who nevertheless care—can claim as their own.

The impetus for Krasny’s search can be found in his childhood. Growing up in a fairly devout Jewish household, where his mother instilled in him an abiding connection to the sacred history of his forebears, Krasny felt a keen sense of connection with God at an early age. He became, for a brief time, a pious Jew, wearing a skullcap on his head and chanting Hebrew prayers at a cantor’s youth club. Later, as he grew older, he became strangely fascinated with Jesus—that is, the Jesus he discovered in Sunday morning Christian television programming and in Christmas carols. “I could sing praises to Jesus without believing in him and without feeling any need for dreidel songs or Jewish rock-of-ages songs to level the song-playing field,” Krasny writes.

It was in college that, like most kids his age, he began to expose his childhood belief in God to the literary and philosophical scrutiny of Flaubert and Tolstoy, Nietzsche and Kierkegaard. While his college experience may have stripped him of the simple spiritualism he grew up with, he was still searching for a way to satisfy his innate spiritual hunger and hesitant about embracing the confident atheism adopted by so many of his peers.

“I wanted my own set of commandments, my own ethical code, my own personal morality, my own certainty, if I could find it, without the necessity of divinely prescribed moral platform.” What Krasny wanted, in essence, was to construct an agnostic credo. And so he spent the better part of his adult life (and most of the rest of the book) doing just that: putting together a kind of agnostic Ten Commandments based a little upon the Torah that he grew up with, a little on the Jesus to whom he’d been introduced as a child, peppered with bits of knowledge from his literary heroes Hemingway and Beckett, Hawthorne and Camus, while borrowing a bit from the East and a bit from the West, a little “Hebraism and Hellenism,” and adding to all of this his own rational experience of the world around him, all in the quest to find—as he puts it—not the God that he’d lost but the one he still hopes to find.

Did Krasny find that God? For that you’ll have read his marvelous book. But suffice it to say that for the agnostic, like the mystic, it is the journey and not the destination that matters most. Indeed, the fundamental problem with agnostics, as Krasny sees it, is that they “cannot help knowing [that] they do not know.” And so, perhaps, the search for knowledge—even knowledge that ultimately can never be attained—is the true spiritual journey upon which all of us should embark.

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Reza Aslan is author of the international bestseller No god but God and Beyond Fundamentalism. His new book, Tablet and Pen: Literary Landscapes from the Modern Middle East, comes out in November. Follow him on Twitter and Facebook.