Changes

Their arrival started the unification process between the various Tau tribes and coincided with the implementation of the concept of the [[Greater Good]]. They first appeared during a siege between the Tau of the plains (later known as the [[Fire Caste]]) and the Tau of the city of [[Fio'taun]] (later known as the [[Earth Caste]]). The Ethereals brought the two sides together to negotiate and convinced them to follow the [[Greater Good]]. Their power over the Tau is such that an Ethereal could tell a Tau to die and that Tau would do so quickly and gladly. The [[Adeptus Mechanicus]] would give much to learn the secret of the Ethereal's power. There is strong implication from the similarities between an organ possessed uniquely among Tau by the Ethereals, and an organ which [[Q'orl]] use in pheromonal communication that this ability may be due to deliberate engineering in the Ethereals' past.{{Fn|1}}

Though the obedience of the Tau to Ethereals is natural, the other races, especially [[Mankind]], have long speculated about the features of this uncommon loyalty. There are a lot of theories from the prenatal indoctrination or pheromonal compulsion to the presence of some veiled psychic gift possessed by the Ethereals, but as yet no confirmed proof of any such power has been secured. Those few Ethereals that have been captured and subjected to interrogation have proven less than forthcoming.{{Fn|8}}