The novel was well received by most readers and critics. Two months after publication, all 210,000 copies of the first printing had been sold. "The New York Times" published two positive reviews of the book: Basil Davenport compared Clarke to Olaf Stapledon, C. S. Lewis, and H. G. Wells, a "very small group of writers who have used science fiction as the vehicle of philosophic ideas." William DuBois called the book "a first rate tour de force that is well worth the attention of every thoughtful citizen in this age of anxiety." Don Guzman of the "Los Angeles Times" admired the novel for its suspense, wisdom, and beauty. He compared Clarke's role as a writer to that of an artist, "a master of sonorous language, a painter of pictures in futuristic colors, a Chesley Bonestell with words". "Galaxy" reviewer Groff Conklin called the novel "a formidably impressive job ... a continuous kaleidoscope of the unexpected."