Technologies in 2001: A Space Odyssey well, such as a nervous breakdown—as Hal did in the film. Clarke noted that, contrary to popular rumor, it was a complete coincidence that each of the letters of Hal's name immediately preceded those of IBM in the alphabet. The meaning of HAL has been given both as "Heuristically programmed ALgorithmic computer" and as "Heuristic ALgorithmic computer". The former appears in Clarke's novel of "2001" and the latter in his sequel novel "2010". In computer science, a heuristic is a programmable procedure not necessarily based on fixed rules, producing informed guesses often using trial-and-error. The results can be false such
2001: A Space Odyssey (film) artist.") John Simon felt it was "a regrettable failure, although not a total one. This film is fascinating when it concentrates on apes or machines ... and dreadful when it deals with the in-betweens: humans ... "2001", for all its lively visual and mechanical spectacle, is a kind of space-"Spartacus" and, more pretentious still, a shaggy God story." Eminent historian Arthur M. Schlesinger, Jr. deemed the film "morally pretentious, intellectually obscure and inordinately long ... a film out of control". In a 2001 review the BBC said that its slow pacing often alienates modern audiences more than it did upon