There are famous challenges to telling the life of Kierkegaard. He died at 42, in Copenhagen, seemingly exhausted after an extraordinary burst of productivity that gave us a flotilla of philosophical texts masquerading as sermons, dialogues, found documents, book reviews. He lived comfortably, financed by his merchant father, and led an almost perversely placid existence, once turning down travel because he was worried it would give him even more ideas. Away from his desk, his primary activity was tramping around the city — his “people baths,” he called them — wearing out the soles of his shoes, “a small, hunched, bright-eyed figure in odd trousers” with a plume of hair that stood out half a foot from his head, a gift to the local caricaturists.

Image Clare Carlisle Credit... John Tresch

He had a childhood habit of secrecy and dissembling, a way to secure inner freedom from a father who demanded total obedience. In his journals he hinted at secrets — family guilt, obscure punishments — that he swore never to divulge. He inked over revealing lines or knifed out pages and burned them. “Kierkegaard in his journals did not talk only to reveal but also to conceal,” Joakim Garff, another of his biographers, observed. He revised his papers as if “planning his own posthumous rebirth.”

A biographer ought to have the instincts of a gaflen. Although Carlisle allows that Kierkegaard “is not an easy traveling companion,” it’s a very polite book she offers us, one that never probes Kierkegaard’s secrets or stoops to speculation. The book ambles along the well-trodden conclusions and avoids engaging with his darker impulses, his own conformism and distaste for democracy. Carlisle follows the critic Georg Lukacs in locating the wellspring of Kierkegaard’s thinking in heartbreak, a broken engagement in his 20s, from which emerged his first book, “Either/Or.” It draws a distinction between two modes of existence (the aesthetic, or sensual, and the ethical) presented as a dialogue between an unrepentant seducer and a family man. Both paths lead to disappointment, he argues. Only in prayer is there solace.

Carlisle does make an unfortunate innovation of her own. She conceives of her book as “a Kierkegaardian biography of Kierkegaard,” following “the blurry, fluid lines between Kierkegaard’s life and writing, and allowing philosophical and spiritual questions to animate the events, decisions and encounters that constitute the facts of a life.” In practice, this gives us a reading experience that feels a bit like the Mad Hatter’s tea party in “Alice in Wonderland,” information flying at us untethered, the courses all out of order.

Carlisle begins in the middle of Kierkegaard’s life and stays trained on him as a young philosopher, displaying an odd indifference to his harrowing childhood. Kierkegaard was the youngest of seven children; his father had prophesied that none of his children would survive past 33, Jesus’ age at crucifixion, and all but Kierkegaard and one brother were to die young. The narrative slips in and out of a breathless present-tense voice with flourishes of soppy characterization: “Writing became the fabric of Kierkegaard’s existence, the most vibrant love of his life — for all his other loves flowed into it, and it swelled like the ocean that crashed restlessly against his native land.” At times Carlisle succumbs to outright fiction. Kierkegaard kept the ring he offered his fiancée and wore it all his life. In the book’s most unrestrained moments, Carlisle imagines his deathbed: “After the light left his eyes the diamond ring Regine had once worn shone on his hand in the moonlight.”