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The Force is a metaphysical and ubiquitous power in the Star Wars fictional universe. It is wielded by characters in the franchise's films and in many of its spin-off books, games, and comics. In the story, the Jedi utilize the "light side" of the Force, while the Sith exploit what is known as the "dark side". The Force has been compared to aspects of several world religions, and the iconic phrase "May the Force be with you" has become part of the popular culture vernacular.

George Lucas created the concept of "the Force" to address character and plot developments in Star Wars (1977). He also wanted to "awaken a certain kind of spirituality" in young audiences, suggesting a belief in God without endorsing any specific religion. He developed the Force as a nondenominational religious concept, "distill[ed from] the essence of all religions", premised on the existence of God and distinct ideas of good and evil. Lucas said that there is a conscious choice between good and bad, and "the world works better if you're on the good side".

Lucas used the term the Force to "echo" its use by cinematographer Roman Kroitor in 21-87 (1963), in which Kroiter says, "Many people feel that in the contemplation of nature and in communication with other living things, they become aware of some kind of force, or something, behind this apparent mask which we see in front of us, and they call it God". Although Lucas had Kroitor's line in mind specifically, Lucas said the underlying sentiment is universal and that "similar phrases have been used extensively by many different people for the last 13,000 years".

The first draft of Star Wars makes two references to "the Force of Others" and does not explain the concept: King Kayos utters the blessing "May the Force of Others be with you all", and he later says "I feel the Force also". The power of the Force of Others is kept secret by the Jedi Bendu of the Ashla, an "aristocratic cult" in the second draft. The second draft offers a lengthy explanation of the Force of Others and introduces its Ashla light side and Bogan dark side. The Ashla and Bogan are mentioned 10 and 31 times, respectively, and the Force of Others plays a more prominent role in the story. In the second draft, "Luke Starkiller"'s mission is to retrieve the "Kiber Crystal", which can intensify either the Ashla or Bogan powers. The film's shorter third draft has no references to the Ashla, but it mentions the Bogan eight times and Luke is still driven to recover the Kiber Crystal. Lucas finished the fourth and near-final draft on January 1, 1976. This version trims "the Force of Others" down to "the Force", makes a single reference to the Force's seductive "dark side", distills an explanation of the Force to 28 words, and eliminates the Kiber Crystal. Producer Gary Kurtz, who studied comparative religion in college, had long discussions with Lucas about religion and philosophy throughout the writing process. Kurtz told Lucas he was unhappy with drafts in which the Force was connected with the Kiber Crystal, and he was also dissatisfied with the early Ashla and Bogan concepts.

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