The “Ark of Truth” is a piece of Alteran technology developed before the Ancients left for the Milky Way. In an attempt to prevent the Ori and their followers rising to power, a device was created that could essentially “brainwash” individuals, for instance Priors, into believing whatever “truth” was programmed into the device. The Ancients’ non-interference policy and belief in free will resulted in the device never being used. Even though the promise of Ascension promised by Origin is a lie, the freedom to believe was something the Alterans ultimately decided they did not have the right to restrict. SG-1 likewise faces the moral and ethical issues raised by the use of the device.

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