One Power

In The Wheel of Time fantasy series by Robert Jordan, the One Power is a supernatural force which some characters can harness to perform feats of (magic). Using the One Power is referred to as channeling, and a character who can do so is referred to as a channeler.

In The Eye of the World, Moiraine Damodred describes the One Power to Egwene al'Vere thus:

“The One Power comes from the True Source, the driving force of creation, the force the Creator made to turn the Wheel of Time. Saidin [/saɪˈdiːn/], the male half of the True Source, and saidar [/saɪˈdɑːr/], the female half, work against each other, and at the same time together to provide that force. Saidin is fouled by the touch of the Dark One, like water with a thin slick of rancid oil floating on top. The water is still pure, but it could not be touched without touching the foulness.

(Rand al'Thor, The Dragon Reborn and Nynaeve al'Meara have cleansed saidin since "Winter's Heart", the 9th book of the series)

Saidar is described as a gentle force, which can only be controlled after surrendering to it. Saidin, conversely, is violent and must be dominated. The taint on saidin had deleterious effects on male channelers' mental and physical health: the more of the Power a man channeled, the faster his condition deteriorated. Since it was cleansed, no more deterioration occurs but what taint already affected the channelers remains.

Angreal are artifacts which enable their users to draw more of the One Power than they would normally be able to. Angreal also protect them from drawing enough Power to burn themselves out.

Sa'angreal are identical to angreal, except that they allow the user to draw more Power than even an angreal can handle. There are at least two Sa'angreal is known to be missing the buffer that prevents the user from drawing more than the channeler can safely use. This is Callandor, pronounced CAH-lahn-DOOR, the sword which is not a sword and Vora's sa'angreal which is a fluted white rod in the possession of the White Tower. The access keys—both ter'angreal—for the two most powerful sa'angreal ever created, the Choedan Kal, are in Rand al'Thor's possession. These allow him to tap into the vast power of the one buried in Cairhien designed for use by men, and another buried on the island of Tremalking designed for women (although the access key for the female Choedan Kal was destroyed during the cleansing of saidin during the ninth book Winter's Heart. At the end of the 12th book the male Choedan Kal itself is intentionally destroyed by Rand Al'Thor by turning its own power against it).

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