Walker Percy was quite emphatic about Fyodor Dostoevsky's influence on his writing. In an interview with Rebecca Presson he stated the matter explicitly.
I suppose my model is nearly always Dostoevsky, who was a man of
strong convictions, but his characters illustrated and incarnated the
most powerful themes and issues and trends of his day. I think maybe
greatest novel of all time is The Brothers Karamazov
almost prophesies and prefigures everything--all the bloody mess and
issues of the 20th century. These three brothers, incarnate in
very deep religious themes, atheism. Ivan Karamazov says: 'If
not exist, all things are permitted. 'All that explains so much
has happened in this century. Dostoevsky forecast communism and what
would take place with the rise of all the ideologies. (1)
In an interview with Phil McCombs, again referring to Ivan Karamazov's statement that "all things are permitted" in a Godless society, Percy added, "but not even Dostoevsky imagined what man without God was capable of" (More Conversations 203). Percy's comment suggests that there are both similarities and crucial differences between the turbulent mid-nineteenth century world of Dostoevsky and Percy's mid-twentieth century western society. Though Dostoevsky was certainly attuned to the increasing impact of science on the social order, he could not have imagined the revolutionary transformation of the world and human consciousness brought about by the growth of technology, which Percy described in his essay "Notes for a Novel about the End of the World." Nor could he have imagined two world wars, the destruction of millions of his fellow Russians in Stalin's gulags, or the development of nuclear weapons capable of the apocalyptic destruction of the planet. Nevertheless, through Ivan Karamazov in The Brothers Karamazov and Nichoil Stavrogin in Demons, Dostoevsky foresaw a future world devoid of belief in a transcendent order of reality, in a metaphysical view of being, or in absolute ethical norms--a world where "all things are permitted." Percy characterized such a world in an interview with Jo Gullidge when he said that "the twentieth century self lives in a post-religious age ... it's post-cosmological, post-mythological, post-Oriental, post-Christian. You're the self and the world, with God more or less omitted these days" (Conversations 294).
In the broadest sense, Percy set out in his writings to imagine the fateful consequences of Dostoevsky's prophesy as manifested in the postmodern, apocalyptic age. In Percy's view, the crisis of the postmodern age is that humans have suffered a spiritual catastrophe--loss of the meaning of existence--leaving them as "deranged" wayfarers alienated from their true selves and from the world. Writing about the present crisis, Percy constantly looked back to Dostoevsky as a model for both themes and narrative strategies. The most pervasive influence and parallels, I believe, are between Lancelot and The Brothers Karamazov, specifically between Lance Lamar and Ivan Karamazov. Despite differences in narrative technique in the two novels, Lance's complex relationship with his listener-friend, Harry/Percival/Father John, echoes Ivan's relationship with his brother Aloysha in four crucial chapters: "The Brothers Get Acquainted" (Book 5, Chapter 3), "Rebellion" (Book 5, Chapter 4), "The Grand Inquisitor" (Book 5, Chapter 5), and "The Devil: Ivan Fyodorovich's Nightmare" (Book 11, Chapter 4). In creating Lance Lamar, Percy fused aspects of the personality and ideology of Ivan, the Grand Inquisitor, and the shabby devil who torments Ivan in his nightmare in order to further develop Dostoevsky's insights about the spiritual crises of modernity--specifically, in order to show the emergence of the postmodern demonic self and its obsession with eroticism and violence as the extreme outcome of Ivan's ideology. Percy pointed to this development in a letter to Lewis P. …