Answer: Orthodox Jews

Spock’s split-fingered salute and the accompanying phrase “Live long and prosper” is about as iconic as iconic gets when it comes to the Sci-Fi genre. What’s especially interesting about the salute and the phrase, which can be interpreted as a Vulcan form of well-wishing and blessing, is that it is derived from a real-world blessing.

In his autobiography, Leonard Nimoy explains that he based the split-finger v-shape on a hand gesture he saw performed as a child when his grandfather took him to an Orthodox synagogue. There he saw, and was impressed by, Jewish Kohanim performing the “priestly blessing” wherein the two hands are held aloft and linked together at the tips of the thumbs.

Years later when he was cast in the role of Spock, he adopted the gesture and sentiment to fit his role as a Vulcan.