Atheis (The Atheist), first published in 1949, portrays the spiritual and intellectual crisis of Hasan, a young Muslim who is raised to be devout but comes to doubt his faith after becoming involved with a group of modern young people. Upon publication, religious thinkers, Marxist-Leninists, as well as anarchists decried the novel for not explaining their ideologies in more detail; but literary figures and many in the general public praised it. The novel, considered to be a masterpiece of modern Indonesian literature, is included in the UNESCO Collection of Representative Literary Works.