At its core, The Bridge of San Luis Rey is a narrative form of theodicy, a philosophical/theological argument that seeks to reconcile the “problem of evil”—that is, the existence of suffering in a world created and governed by an all-good, all-powerful God (as God is understood in the Abrahamic tradition). Brother Juniper’s treatise, which is referenced throughout the work, falls firmly within this tradition of Christian apologetics, as witnessing the bridge’s collapse prompts him to ask, “Why did this happen to those five?” (4). His subsequent investigation is an attempt to prove a divine pattern in the tragedy, to demonstrate scientifically that “we live by plan and die by plan” (4). This inquiry mirrors real-world efforts to find meaning in catastrophes, such as the devastating 1755 Lisbon earthquake. The earthquake, which killed tens of thousands on a major Catholic holiday, prompted intense debate among European thinkers like Voltaire, who satirized the idea that such random horror could be part of a benevolent divine order in his 1759 novella Candide.

The Bridge of San Luis Rey is sympathetic to this view. Brother Juniper’s quest to prove God’s justice ultimately fails; his book is declared heretical and burned in an irony that exemplifies the novel’s lightly satirical attitude toward the endeavor. That said, the novel is not as strident in tone as a work like Candide. The philosophical exploration at its heart was deeply personal for Wilder, who was raised by a strict Calvinist father. The Calvinist branch of Christianity, which today encompasses denominations including Presbyterianism and Reformed Christianity, has historically heavily emphasized the doctrine of predestination, or the belief that the salvation or damnation of the individual soul is predetermined by God. This was a concept Wilder wrestled with, and the novel transforms his theological doubts into a humanistic inquiry, ultimately suggesting that meaning is not divinely ordained but created through human connection. As the abbess concludes, “There is a land of the living and a land of the dead and the bridge is love, the only survival, the only meaning” (83).