The Vulcan salute first appeared in 1967 on the Star Trek second season opening episode, "Amok Time". The gesture famously has a reputation for being difficult for some people to make without practice or the covert pre-positioning of the fingers, and actors on the original show reportedly had to position their fingers off-screen with the other hand before raising their hand into frame. This reputation may stem from variations in individuals' manual dexterity ... In his autobiography I Am Not Spock, Nimoy wrote that he based it on the Priestly Blessing performed by Jewish Kohanim with both hands, thumb to thumb in this same position, representing the Hebrew letter Shin (ש), which has three upward strokes similar to the position of the thumb and fingers in the salute. The letter Shin here stands for Shaddai, meaning "Almighty (God)". Nimoy wrote that when he was a child, his grandfather took him to an Orthodox synagogue. There he saw the blessing performed and was very impressed by itComment: Interesting.