Alfred Korzybski (July 3, 1879 - March 1, 1950) was a Human philosopher. He coined the phrase "A difference which makes no difference is no difference." In the year 2269, Montgomery Scott quoted this phrase when talking with Leonard McCoy about whether or not transporters actually created identical duplicates of people then destroyed the original body, and if the soul was also duplicated; he also mentioned that Spock was fond of quoting this phrase. Two weeks later, when a nearly identical duplicate of Spock was created, he quoted this phrase to James T. Kirk to justify allowing the two Spocks to co-exist. (TOS novel: Spock Must Die!)