Shai (also spelt Sai, occasionally Shay, and in Greek, Psais) was the deification of the concept of fate in Egyptian mythology. As a concept, with no particular reason for associating one gender over another, Shai was sometimes considered female, rather than the more usual understanding of being male, in which circumstance Shai was referred to as Shait (simply the feminine form of the name). His name reflects his function, as it means (that which is) ordained.
As the god of fate, it was said that he determined the span of each man's life, and was present at the judgement of the soul of the deceased in duat. In consequence, he was sometimes identified as the husband of Mesenet, goddess of birth, or, in later years, of Renenutet, who assigned the Ren, and had become considered goddess of fortune. Because of the power associated in the concept, Akhenaten, in introducing monotheism, said that Shai was an attribute of Aten, whereas Ramses II claimed to be lord of Shai (i.e. lord of fate).
During Ptolemaic Egypt, Shai, as god of fate, was identified with the Greek god Agathodaemon, who was the god of fortune telling. Thus, since Agathodaemon was considered to be a serpent, and the word Shai was also the Egyptian word for pig, in the Hellenic period, Shai was sometimes depicted as a serpent-headed pig, known to Egyptologists as the Shai animal.
Shai (, an acronym for Sherut Yediot , lit. Information Service), established in 1940, was the intelligence and counter-espionage arm of the Haganah and the forebear of the Military Intelligence Directorate in Mandate Palestine.
During World War II the British Special Operations Executive supplied the Haganah with weapons, training and funding, and the Haganah provided linguistic experts and operatives. The British provided commando training for special operations to both Shai operatives and FOSH veterans through a training school designated ME 102, which was set up by MI4.
Following the defeat of Nazi Germany, "... until 1948 the SHAI's primary objectives included the promoting of an independent Israeli state; infiltrating British mandate offices in order to inform the Jewish and Zionist leadership of British attitudes and proposed actions; collecting political information that could be used as propaganda; penetrating Arab and anti-Zionist factions in Palestine and abroad; and providing security for the arms-smuggling and illegal immigration programmes of the Haganah."
David Shaltiel was appointed head of SHAI in April 1946, he was succeeded by Isser Be'eri in February 1948.
By 1948 Shai had 68 staff members, 60 British and Jewish agents, 80 Arab agents, and spent almost $700,000 per year. It was responsible for protecting Ta'as, the clandestine munitions industry and Rekhesh, the arms procurement organisation.
Famous Shai operatives included Reuven Shiloah and Nahum Admoni. The Shai was one of five intelligence agencies set up by David Ben-Gurion, the others being the internal security agency Shin Bet, the Aliyah Bet, responsible for smuggling immigrants, and the police intelligence forces.